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In the next 4 minutes, you will read everything you need to know about the Best Thermos Flask in India in 2023.
For those who do not know, a thermos flask is also known as a vacuum flask or a dewar flask.
With a good quality thermos flask, you will not have to worry about water getting hot in summers or tea getting cold in winters.
What is a thermos flask?
A thermos flask is an insulated bottle which helps to keep the hot liquids hot and cold liquids cold for 12-24 hours. The capacity of a thermos flask starts from 500 ml and can go up to 1.5 litres.
If you are short on time, Milton Thermosteel Flask is the best thermos flask for tea and coffee in India, this flask comes with a cover and a cup too. Also, InstaCuppa Thermos Bottle is the best hot and cold water bottle in India in 2023.
To understand, what is a Thermos Flask, how does it work, Borosil vs Milton flask which is better, and how to choose the best thermos flask in India, you can skip down to our “Buying Guide”.
So, today in this post we will review the Top 10 Best Thermos Flask in India in 2023, compare them in terms of their pros and cons and which one should you buy for water, milk, tea or coffee.
You can use these best quality thermos flasks for work, college, school, hiking, etc.
You can also jump directly to the “Reviews” or the “Top 3 Picks“ of these Top 10 Best Thermos Flask in India in 2023.
Top Brands
1. Milton
2. Cello
3. Borosil
4. InstaCuppa
5. Amazon Solimo
6. Dubblin
7. Traniac
8. Unigear
9. Frabble
10. Incrizma
There are over 20 thousand thermos flasks available in India. Needless to say, the number of brands selling these thermos flasks will also be huge.
A good brand is one that is durable, sturdy, has robust performance and most importantly, can be trusted. When we take all these factors into consideration, we could gage that Milton, Cello, Borosil and Instacuppa are the best thermos flask brands in India.
1. Milton
Milton does not need any introduction in the Indian market. I think most of us can relate to the school days in the 90s (those were my school days, not sure about yours) when kids used to bring Milton water bottles and those were considered premium water bottles. Well guess what, it’s been 30 years, Milton still leads the Indian market when it comes to the lunch boxes, water bottles or thermos flask.
Capacity of a Milton thermos flask in India varies from 350 ml to 2,000 ml while price ranges between 300 rupees to 3,000 rupees. In 2023, the Best Milton Thermos Flask in India is Milton Thermosteel Flip Lid Flask with 1,000 ml capacity and a 1 year warranty.
2. Cello
Cello similar to Milton is a brand that we recognise from the school times. In India, Cello deals in lunch boxes, water bottles and everything from your household essentials to the office supplies. The brand is known for its reliability, quality and robust performance.
Capacity of a Cello thermos flask in India varies from 350 ml to 2,000 ml while price ranges between 200 rupees to 2,500 rupees. In 2023, the Best Cello Thermos Flask in India is Cello Swift Stainless Steel Flask with Double walled protection and 1,000 ml capacity.
3. Borosil
Borosil is one of the India’s most trusted glassware brand since 1962 and deals in microwave safe glass bowls, lunch boxes, dinner sets, tumblers, storage containers, water bottles and other kitchen appliances. You can trust this brand in terms of quality and also their products are quite affordable.
Capacity of a Borosil thermos flask in India varies from 400 ml to 2,000 ml while price ranges between 600 rupees to 1,200 rupees. In 2023, the Best Borosil Thermos Flask in India is Borosil Hydra Thermo Stainless Steel Flask. This flask comes with a thermal cover, a capacity of 1,000 ml and is one of the best thermos flask in India under 1,000 rupees.
4. Instacuppa
Instacuppa is a new addition to the Indian market and is a brand that hails from the South of India. The reason I have included Instacuppa in the list of best thermos flask brands in India is because I bought one of their thermos flasks last year when the lockdown had started in India. As I was working from home, I wanted to focus on my water intake especially due to summers and I am glad I made the right choice.
I have infact reviewed one of their Thermos Flasks (the same one I bought for personal use), you can check that review here. Though their products are a bit on the expensive side, but their intent is to minimise the use of plastic and go for healthy alternatives, like bamboo or glass.
Capacity of an Instacuppa thermos flask in India varies from 500 ml to 1,000 ml while price ranges from 800 rupees to 1,700 rupees. In 2023, the Best Instacuppa Thermos Flask in India is Instacuppa Thermos Bottle 1000 ML with Straw Lid.
Comparison
Best Thermos Flask Capacity Hot/Cold Warranty Ratings Check Price Milton 1000 ml 24 hours 1 year 5/5 Cello 1000 ml 24 hours NA 4.8/5 Amazon Solimo 1000 ml 24 hours 1 year 4.8/5 Traniac 1000 ml Hot/Cold - 13/36 hours 1 year 4.9/5 Unigear 500 ml Hot/Cold - 12/24 hours NA 4.8/5 Borosil 1000 ml 24 hours 1 year 4.9/5 Frabble 8 500 ml Hot/Cold - 12/24 hours NA 4.7/5 Instacuppa 1250 ml Hot/Cold - 12/24 hours 1 year 5/5 Dubblin 1000 ml Hot/Cold - 12/24 hours 1 year 4.9/5 Incrizma 500 ml Hot/Cold - 12/24 hours NA 4.9/5
Editor’s Pick
Best Thermos Flask Premium Pick Best Pick Budget Pick Flask Thermos Flask Capacity 1000 ml 1250 ml 1000 ml Features Cold - 36 hours, Hot - 13 hours Cold - 24 hours, Hot - 12 hours Hot/Cold - 24 hours Buy Now
Reviews
1. Milton Thermosteel Flip Lid Flask, 1000 ml Reviews
1st flask in our review of Best Thermos Flask in India in 2023 is a 1,000 ml thermos flask from the house of Milton.
If you are simply looking for the best thermos bottle for hot water in India, look no further than Milton.
Without a doubt, Milton is one of the best thermos flask brands in India. The reason I can say this is it is one of the bestselling thermos flasks in India with maximum positive customer reviews and ratings.
This is a double walled thermos flask where both the inner and outer steel are vacuum insulated to keep your beverages at a constant temperature.
This thermos flask from Milton can keep your water cold and hot for 24 hours, which is massive and pretty useful too.
This is as per what Milton is claiming, but you can be sure about at least 18-20 hours of temperature retention.
When we used this bottle, we were more than satisfied in terms of its heat retention and also there was no odour from the bottle.
The inside of the thermos flask has a copper coating for better heat retention. As an extra utility, you can use the lid of this flask as a cup for drinking, this way you will not have to carry an extra cup while travelling.
One word of caution, if you see Milton written on the flask and Milton Thermosteel written on the box, don’t be surprised.
The only issue that could have been improved in this Milton thermos flask is the weight.
This flask weighs around 700 grams which is quite heavy as compared to the other bottles (only Borosil and Milton flask has this weight).
Nevertheless, with a carry pouch and a 1-year warranty, I will definitely bet my money on the best thermos flask in India in 2023 for hot and cold water from Milton and that too under 1,000 rupees.
If you are looking for a bigger capacity thermos flask, you can also check out the 1800 ml flask from Milton that can keep your water hot and cold for 24 hours and has a 1-year warranty too.
In a nutshell, if you have been searching for the best thermos bottle for tea in India under 1000 rupees, you can buy Milton Thermosteel Flip Lid Flask.
Product Specifications:
Capacity – 1,000 ml
Colour – Silver
Weight – 700 grams
Dimensions – 33.27 x 9.78 x 9.78 cm
Temperature Retention – 24 hours
Pros of Milton Thermosteel Flip Lid Flask:
Best thermos flask in India under 1,000 rupees
100% rust free
1 year warranty
Spill free and airtight flip lid
Leak resistant
BPA free
Ideal for Gym, Sports, School, Outdoors
Cons of Milton Thermosteel Flip Lid Flask:
A bit heavy for travelling
2. Cello Swift Stainless Steel Flask, Double walled, 1000 ml Reviews
Cello similar to Milton is one of the best thermos flask brands in India and in terms of price, it is quite affordable too.
In fact, Cello is one of the best thermos flask to buy online in India, if you do not want to spend too much on a thermos bottle.
The stainless steel thermos flask from Cello comes with a small mouth and neck, which is apt for spill free drinking. The small mouth and neck also helps to restrict the escaping of heat from the inside.
The thermos flask from Cello has a modern click press inner lid, ideal to seal and retain the temperature levels.
The flask itself is made from thermo seal technology and has an additional layer of insulation because of its thermal jacket.
The flask from Cello has an air tight plastic cap and during our tests of the best thermos flasks, we observed that this Cello flask is able to retain the temperature for approx. 18 hours.
There is a lot of choices in terms of colours and capacity when it comes to Cello Thermos flask.
You can choose anywhere from 350 to 1,800 ml. Also, this flask is available in Silver, Blue and Red colour.
But as a recommendation, don’t go for any colour except Silver as colours like Blue and Red will loose its shine in a few months.
Unlike Milton Thermosteel flask, you do not get a carry pouch or a 1-year warranty which is the only thing that we didn’t like in this Cello thermos flask.
If you are only looking for a Cello flask with a warranty, then you can go for Cello Flip Style Stainless Steel Bottle Hot and Cold.
With a minimum 18 hours hot and cold retention, this thermos flask from Cello is truly the best thermos flask for hot and cold water in India in 2023.
Product Specifications:
Capacity – 1,000 ml
Colour – Silver, Blue and Red
Weight – 360 grams
Dimensions – 9 x 34 x 10 cm
Temperature Retention – 24 hours
Pros of Cello Swift Stainless Steel Flask:
Lightweight
Robust and durable thermos flask
Best thermos flask in India under 1,000 rupees for hot and cold water
100% insulated vacuum steel
Inside copper coating for better heat retention
Food grade and leak proof steel
BPA free
Ideal for gym, office, school or any outing
Cons of Cello Swift Stainless Steel Flask:
No warranty
No carry pouch
3. Amazon Brand – Solimo Thermal Stainless Steel Flask Reviews
Solimo is Amazon’s own in house brand in India and is known for its affordable products in every niche in the Indian consumer industry.
This is a 1,000 ml thermal stainless steel flask that can retain hot and cold temperatures for around 24 hours as claimed by Amazon, we will come back to that later.
This thermos flask comes with an Anti-drip push open lid to prevent leakages and its double walled flask prevents moisture and steam on the outside even when filled with hot or cold liquids.
Similar to Milton, this flask from Amazon has a twist cap that you can use as a small cup to consume or taste your beverages.
The good thing is you get a 1 year warranty as well as carry pouch with the Amazon thermos flask.
There is a lot of choice in terms of patterns, for example Amazon Solimo has another thermos flask that comes with flip top. Also, there is a curved and then there is a straight style thermos flask.
It seems Amazon has done everything to make this thermos flask a big hit in the Indian market except for one thing.
If you are expecting this flask to retain temperature for more than 15 hours, I recommend you go for Milton or Cello because my experience with Amazon flask wasn’t that good in terms of heat retention.
Moreover, the thread quality of the thermal cover wasn’t up to the mark as I could see threads opening up in a week, and it did not look very good.
Product Specifications:
Capacity – 1,000 ml
Colour – Silver
Weight – 500 grams
Dimensions – 37.4 x 10.4 x 9.6 cm
Temperature Retention – 24 hours
Pros of Amazon Brand Flask:
1 year warranty
Push-button anti-drip mechanism
Twist cap cup
1 carry pouch
Strong body and exterior
Cons of Amazon Brand Flask:
Temperature retention isn’t that great
Thermal cover quality is just average
4. TRANIAC Double Walled Vacuum Insulated Stainless Steel Flask Reviews
This is an interesting thermos flask from TRANIAC which is quite popular these days. Traniac is also the best quality thermos flask in India available in 2023.
To start with, this thermos flask has a very impressive sporty design making it a perfect fit if you are looking for a thermos flask for gym, sports or outdoor activities.
The thermos flask is made from Stainless Steel with Silicone Rubber Grip, which is very useful for a comfortable grip.
The capacity of this flask is 1,000 ml and the best part is this flask can retain hot water for up to 13 hours and cold water up to 36 hours which is literally the highest in all the thermos flasks.
When we tested this flask in terms of temperature retention which we did only for cold water, the flask was able to keep the water cool for more than 24 hours which was mind blowing.
The flask also features a screw-on, leakproof lid with a wider mouth, perfect for ice cubes or take big sips of beverages.
The lid of the thermos flask is made from silicon and is very ergonomic, plus you also get a free additional lid when you order the thermos flask.
The lid is semi-circular in shape which is good for grip when you are walking, running, and you will find rubber grips on both the lid handle and on the bottom part of a bottle.
The bottom grip is good and will be handy to prevent the bottle from slipping.
In my opinion, the feel of this bottle is premium and is different from other thermos flasks in India.
Even though this flask is a bit on the expensive side, but with such a premium look, 1 year warranty and excellent temperature retention properties, I don’t mind paying an extra few hundred bucks.
If you have been looking for a thermos flask that is ideal for gym, trekking, hiking and other sports activities, you can undoubtedly go for TRANIAC thermos flask as it is the best thermos flask in India for gym, hiking, mountaineering, etc.
Product Specifications:
Capacity – 1,000 ml
Colour – Matte Black
Weight – 580 grams
Dimensions – 32.4 x 10.3 x 10.2 cm
Temperature Retention – Hot/Cold – 13/36 hours
Pros of TRANIAC Flask:
1 year warranty
Unconventional thermos flask
Leak proof, BPA free
Rubber grip
1 extra rubber lid
Excellent temperature retention
Double powder coating for durability
Ideal for sports, gym and outdoor activities
Cons of TRANIAC Flask:
A bit expensive
No pouch to carry the bottle
5. UNIGEAR Premium Stainless Steel Sports Thermos Flask Reviews
Unigear is a registered trademark and protected by the Office of Controller General of Patents, Designs and Trademarks, Government of India.
If you are tight on budget and looking for the best thermos flask in India under 500 rupees, you can pick Unigear Sports Thermos Flask.
This thermos flask comes in a capacity of 500 ml with a very sporty and vibrant look.
The material of the flask is stainless steel and features a double wall vacuum insulated technology.
During our tests, we found out that this flask can easily retain cold temperatures for up to 16-18 hours, which is fabulous considering the price of this bottle.
The bottle has a wide mouth which allows you to take big sips at a time and even pour in some ice cubes if you have cold beverages in the flask.
Since the bottle is made from food grade steel, you don’t have to worry about any chemicals or metallic taste.
One word of advise, don’t pick this thermos flask only because the colour or exterior design is attractive as it’s a sticker which will peel off over the course of regular usage, but you can rely on the matte finish which seems pretty solid.
What I feel could have been improved about the Unigear Thermos flask is the choice of different sizes, there is no 750 ml or 1,000 ml variant, just the 500 ml variant.
Plus, there is no warranty on this flask but considering this price I’ll give this thermos flask 8/10. Overall, the best thermos flask in India in 2023 under 500 rupees.
Product Specifications:
Capacity – 500 ml
Colour – Blue, Orange and Green
Weight – 360 grams
Dimensions – 23.8 x 7.6 x 7.4 cm
Temperature Retention – Hot/Cold – 12/24 hours
Pros of UNIGEAR Premium Sports Thermos Flask:
Most affordable thermos flask in India
Unconventional thermos flask with a very vibrant look
Rust resistant
Leak proof, BPA free
Rubber grip
Ideal for sports, gym and outdoor activities
Cons of UNIGEAR Premium Sports Thermos Flask:
Does not have a 1,000 ml flask, only 1 size available in 500 ml
No warranty
6. Borosil Hydra Thermo Stainless Steel Flask Reviews
Borosil is one of the most reputed and best thermos flask brands in India.
This is a 1,000 ml Hydra Thermo Stainless Steel Flask that comes with a black thermal cover which is good for holding and carrying this flask from one place to another.
This thermos flask has a double wall insulation and can keep your water hot and cold for 24 hours.
For those who are looking to buy a flask with a warranty, Borosil Hydra Thermo flask can be a good choice as you get a 1 year warranty.
The interior and exterior of this flask is made from food grade 304 stainless steel, which is rust free too. All the plastic parts are food grade and non-toxic for healthy consumption.
In order to ensure temperature is retained for longer periods, this flask has a copper coating inside. The cap of the flask is leak proof and can be doubled as a cup to drink small quantities of water.
The good thing is Borosil has kept different consumer demands in mind while creating this flask as you can choose from 500ml, 700ml to 850ml.
You will not have any trouble while carrying this flask as the exterior thermal cover has a cotton handle.
All said and done, this bottle is from an Indian company, but is made in China for reasons unknown.
As far as the performance is concerned, it is top notch and one of the best thermos flask in India for hot and cold water.
You can also check out this black colour thermos flask from Borosil with a capacity of 850 ml, with a 1 year warranty.
Product Specifications:
Capacity – 1,000 ml
Colour – Silver
Weight – 570 grams
Dimensions – 8.4 x 8.4 x 31 cm
Temperature Retention – 24 hours
Pros of Borosil Hydra Thermo Stainless Steel Flask:
1 year warranty
Thermal cover protection
100% rust proof
Leak proof, BPA free
Ideal for office and personal use
Cons of Borosil Hydra Thermo Stainless Steel Flask:
Made in China
7. Frabble8 Double Wall Thermos Flask Reviews
For all those people who are looking for a thermos flask as well as a multi-functional steel infuser that you can use for loose tea leaves, fruits infusion, tea bags and your favourite mocktails, this is the product you should go for.
This is a 500 ml thermos flask from Frabble 8 that can retain hot temperatures for up to 12 hours and cold temperatures for up to 24 hours.
The flask has a very sporty design and comes in a midnight black colour. The inside of the flask is double walled insulated and is made from rust-resistant food-grade stainless steel.
The 500 ml thermos flask features a wide mouth which is good to pour in some ice cubes in the summer.
It also comes with a textured grip for sweat-free usage. What we liked about this thermos flask is the addition of mesh infuser which can be used for infused drinks, shakes, etc.
The matte finish on the flask body will help you to hold it comfortably and even for longer durations.
Another thing you should know is the temperature retention with this thermos flask, we felt that over a period of 2 weeks, the number of hours for which this flask was able to retain temperature came down to around 60-70%, which was indeed a bummer.
Product Specifications:
Capacity – 500 ml
Colour – Midnight Black
Weight – 350 grams
Dimensions – 24.2 x 7.4 x 7.3 cm
Temperature Retention – Hot/Cold – 12/24 hours
Pros of Frabble8 Double Wall Thermos Flask:
18/8 stainless steel body
Durable and scratch resistant body
Leakproof bottle
Tea Infuser
Anti-slip cup bottom
Ideal for office, home, gym, car and school
Cons of Frabble8 Double Wall Thermos Flask:
No warranty
No choices of bigger sizes, only 500 ml available
Temperature retention is just average
8. InstaCuppa Thermos Bottle 1250 ML Reviews
InstaCuppa is a recent addition to the thermos flask industry and is truly classified as one of the best thermos flask brands in India.
I ordered this thermos flask from Instacuppa last year when the lockdown had started. Initially, I found the price to be a bit on the expensive side, but trust me it was worth every penny.
You can also check out my comprehensive and detailed review on the InstaCuppa thermos bottle.
To keep it short here, I’ll mention the most important things you should know about this flask. It comes in a 1,250 ml capacity and two colours – Black and Blue.
The material of the flask is made from premium stainless steel, and you will know that this bottle is going to last for years to come the moment you touch it.
The cold water will indeed stay cool for 24 hours and hot water for 12 hours, may be even more.
With a weight of 500 grams, this flask is a bit on the heavier side but with a slip-resistant surface, this flask will not slip from your hands.
When I ordered this bottle last year, it only came in 1,000 ml variant, but as of now InstaCuppa is offering a 550, 700, 1000 ml and 1250 ml variants.
As far as the looks are concerned, this is one of the most good looking thermos flasks you will find in India in 2023 and that too with a 1 year warranty.
When I say good looking, I am referring to the elegance and class this bottle has with a very subtle plain black matte finish, one can tell by the looks that this flask is expensive.
The only thing that InstaCuppa could improve in this thermos flask is that it comes with a plastic straw inside.
To sum it up, you can buy InstaCuppa Thermos Flask with your eyes closed as it is undoubtedly one of the best thermos flask in India in 2023 for hot and cold water.
You can also check out the InstaCuppa Insulated Thermos Infuser Water Bottle 1 Litre, it comes with 2 lids and has a 1 year warranty.
Overall, if you are looking for a high quality and best thermos flask for keeping drinks hot and cold in India, you can certainly choose InstaCuppa.
Product Specifications:
Capacity – 1,250 ml
Colour – Blue and Black
Weight – 500 grams
Dimensions – 31.8 x 10.4 x 10.2 cm
Temperature Retention – Hot/Cold – 12/24 hours
Pros of InstaCuppa Thermos Bottle:
1 year warranty
Made in India
Excellent temperature retention
Leak proof
Strong and robust flask
Durable and will last for many years to come
Premium looks with a very classy exterior
Ideal for office, home, gym, car and school
Cons of InstaCuppa Thermos Bottle:
A bit expensive
9. Dubblin Vintage Premium Thermos Flask Reviews
Another thermos flask I have personally tried and bought last year. In fact, this flask from Dubblin is the best vacuum flask in India for keeping milk, tea, water, etc. hot and cold for hours.
After ordering InstaCuppa thermos flask for my own use, I ordered a 900 ml variant of Dubblin thermos flask for my mother in summers, well it didn’t last long as my mother left it somewhere after using it for a couple of months.
However, the good news is this thermos flask is quite sturdy and good at what it does.
It can keep and maintain the temperature for 12/24 hours – hot/cold beverages.
The look and feel of this flask is quite classy especially in the black colour.
The double walled vacuum flask is made from 18/8 stainless steel while the plastic lid is made of food grade material.
The anti-skid bottom ensures total protection as the thermos flask will not slip from the surface.
There is a colour choice of silver, golden and black, but I recommend going with black colour as it looks quite classy.
The 1 year warranty is an icing on the cake and all these features make the Dubblin thermos flask the best thermos flask in India under 1,000 rupees in 2023.
Product Specifications:
Capacity – 1,000 ml
Colour – Blue and Black
Weight – 470 grams
Dimensions – 9 x 9 x 31.8 cm
Temperature Retention – Hot/Cold – 12/24 hours
Pros of Dubblin Premium Thermos Flask:
1 year warranty
Made in India
Reliable temperature retention
Anti-skid bottom
Premium looks
Ideal for office, home, gym, car and school
Cons of Dubblin Premium Thermos Flask:
No carry pouch or thermal cover
10. Incrizma Smart Vacuum Insulated Water Bottle Reviews
The last product in our review of Best thermos flask in India in 2023 is a digital thermos flask from Incrizma.
This is a 500 ml thermos flask that comes with LED temperature display, kudos to Incrizma for this innovation.
This is a vacuum insulated bottle that can maintain cold temperatures for 24 hours and hot temperatures for 12 hours.
The material is 304 stainless steel and of food grade quality.
You can check the current temperature of your beverages with a slight touch on this bottle, and you will see it instantly on the LED panel.
The LED Temperature display will last up to 80,000 touches without a battery change, this is approximately 5 years of usage for you.
With a silicon anti-slip pad, you can keep this flask anywhere, and it will not fall unless you push it with force.
The inclusion of a stainless steel tea filter adds more value and utility to this thermos flask. As far as the cleaning is concerned, you can easily do it as the thermos flask is waterproof.
What we didn’t like in this thermos flask is the price is a bit too high for a 500 ml variant and even then, there is no warranty to justify the price.
This thermos bottle will suit your requirements if you are looking for a flask that has a few digital capabilities too.
In terms of the heat retention, this thermosteel bottle is quite impressive and certainly the best insulated thermos for tea and coffee in India in 2023.
Product Specifications:
Capacity – 500 ml
Colour – Black
Weight – 340 grams
Dimensions – 24.38 x 8.13 x 7.62 cm
Temperature Retention – Hot/Cold – 12/24 hours
Pros of Incrizma Insulated Water Bottle:
LED display temperature
Comes with a tea filter
Food grade silicon seal
Anti-skid pad
Ideal for school, college and office
Cons of Incrizma Insulated Water Bottle:
A bit overpriced for 500 ml flask, due to the digital LED display
No warranty
Which is the Best Thermos Flask in India in 2023
Buying Guide
With the advancement in technology, we have seen so many changes in what we have used in the past and what we currently use in our daily lives.
Taking the instance of a water bottle, back in the 90s we used to keep those heavyweight water bottles with the belt and a straw, and we then moved to lightweight plastic bottles. It was after plastic bottles, brands started coming up with insulated bottles where water will stay cool for a longer period.
In 2023, we have thermos flasks which are way better in maintaining constant temperatures. But the question is what is a Thermos Flask, how does it work and how to choose the best thermos flask, let’s find it out in this Buying Guide today.
What is a Thermos Flask?
The word Thermos is derived from the Greek word “Therm” which means heat. Similarly, the word flask means a container with a closure. It was during 1892 when the Scottish scientist Sir James Dewar invented the vacuum flask while he was trying to keep a chemical at a stable temperature which was placed in a flask.
To accomplish this, the Scottish scientist placed a glass bottle within another larger glass bottle, and evacuated the air between the two bottle walls. This led to the creation of a partial vacuum to keep the inside temperature constant.
Several years passed by with one experiment after the another and this is how, “Thermos flasks” were introduced in our daily lives.
The main job of a thermos flask is to keep the hot contents hotter and cool contents cooler. The longer heat or cold can be retained, the better a thermos flask is.
Other features such as wide mouth, so you can easily fill the bottle or scoop in a few ice cubes, leak-proof lids, lightweight, etc further adds to the value of a thermos flask. To understand this more, one has to know how a thermos flask works and this is exactly, what we are going to discuss next.
You can also check Wikipedia article on the functioning of Thermos Flask.
How does a Thermos Flask works?
Working of a thermos flask is not as difficult as how it looks or sounds. To understand the working mechanism of a thermos flask, we will need to get into a little bit of science.
If you are able to recall what you read in the school text books, there are 3 ways through which heat can be transferred, these 3 ways are Conduction, Convection and Radiation.
Without getting into the detailed definitions of Conduction, Convection and Radiation, I will explain how does a thermos flask work.
If you see the layout of a thermos flask, you will notice there is a metal case separated by 2 layers of glass with a vacuum in between. The glass here is lined with a reflective metal layer.
Instead of metal, there can be layers of stainless steel as well depending on the type of flask. Lastly, there’s a stopper, tight screw on the top.
Now, all these built-in features prevent the heat transfer by Conduction, Convection and Radiation. Here’s how, the vacuum prevents conduction, there is a stopper on the top that prevents air from entering or leaving the thermos flasks, so chances of convection are impossible too.
When it comes to radiation, when it tries to leave the hot liquid, the reflective lining reflects it back in again. So, there is literally no heat transfer from a vacuum flask and the same method applies for cold drinks or beverages too.
To sum it up, a thermos flask does not allow heat transfer by any of the 3 ways the heat can travel i.e. Conduction, Convection and Radiation and this is how, your hot drink remains hot even after hours and cold beverages remain cool after hours.
The Scottish physicist James Dewar understood this science and came up with the concept of vacuum flask, a container with an inside and outside wall separated by a vacuum.
How We Tested the Best Thermos Flask in India
If you check Amazon or Flipkart, you will see thousands of thermos flask available. Milton, Cello, Borosil etc are some of the best thermos flask brands in India.
The problem is each of these brands have around 10-20 flasks available with very minor differences between them. This makes it a little difficult for the consumer to pick one best thermos flask amongst a thousand others.
So, we filtered out the brands which were not very good, does not have good customer reviews, or the brand is unknown and unreliable. After this we were left out with around 20 thermos flasks.
We tested these 20 flasks with hot and cool beverages to see which one is able to retain the temperature for the longest duration. Once we were able to figure out the heat loss for our hot test and heat gain for our cold test, we were left with only 14 flasks.
The next and final thing we did was to use these flasks the way you would for 14 days. This included checking every small aspect such as how easy these flasks are to drink from, close, open, toss in a bag, ease of cleaning or maintenance.
This final step helped us to reduce 4 more flasks and that’s how we were left with the Top 10 Best Thermos Flask in India in 2023.
How to Choose the Best Thermos Flask
With a choice amongst more than 20,000 flasks in India and that too with different shapes, features, design, size, etc it can be a bit difficult to make the right choice. Ideally, you should pick a thermos flask depending on the drink you are going to carry in it. Along with it, there are some more factors you should know before buying a thermos flask, let’s take a look at it.
1. Temperature Retention: What good your thermos flask is if it cannot even retain the temperature for a while, hence temperature retention is the most important factor before buying a Thermos flask. If you go for a cheap thermos flask, they will cost you around 300 rupees, but they will not be able to maintain the temperature for more than 3-4 hours, which is useless. Hence, pick the high quality thermos flasks as they can retain and maintain temperatures for minimum 18-20 hours and gives you full value for the money. The most important factor that influences the temperature retention is the double wall vacuum insulation. In a nutshell, always go for a thermos flask that has a double wall insulation.
2. Types of Insulation: There are 2 types of insulation used in a thermos flask – vacuum and foam based. As you can know, vacuum insulation works by restricting the transfer of heat from the outside to the inside of the bottle. This is done with the help of a vacuum. When it comes to foam based insulation, foam helps in preventing the convection and due to the presence of foam, it gets very difficult for the air to move around. When you compare these 2 types of insulation technologies, vacuum based flasks can retain the temperature for longer periods in comparison to foam based flasks. Thus, you should go for a vacuum a.k.a thermos flask.
3. Types of Material: Between plastic and stainless steel, plastic is cheaper in terms of construction, but they are not very good insulators and can only retain the temperature for 3-4 hours. While buying a thermos flask, always choose double-walled stainless steel material as it is not just the best material in terms of temperature retention, but is also sturdy, durable, scratch resistant, rust resistant, etc. The thumb rule is your flask should not get hot while you pour in the hot beverage.
4. Capacity: Capacity of a thermos flask in India varies from 300 ml to 2 litres. Depending on what your use is, you can pick a thermos flask. For an example, if you are buying a thermos flask for your kids, picking a 500 ml flask should be good. On the other hand, if you are buying a thermos flask for yourself, pick the one that comes with at least 1,000 ml capacity.
5. Food Grade Material: Some of the flasks use a straw for easy consumption of the beverage. That straw could be made from plastic, I personally have not seen a straw made from steel. Ensure that plastic is food grade plastic and is not toxic. Generally, branded flasks already take care of all these things, for example you will steel used in their bottles is 304 food grade stainless steel.
6. Design: If I only need a thermos flask for gym, sports, outdoor activities such as trekking, hiking I will go for a flask which has a sporty look such as the TRANIAC flask. But on the other hand, If I need a flask that I am going to use in the office, I will go for a minimalistic design that is offered by Milton, InstaCuppa, etc. Lastly, for a school or college going adult, the Incrizma flask with LED temperature display will be so cool. Hence, pick a flask depending on your requirements.
7. Opening of the Cap: The diameter of the cap is an important aspect in choosing a thermos flask. You don’t want to end up buying a flask with a very narrow open passage through which you cannot even scoop in the ice cubes. At the same time, the mouth of the flask should not be too wide which will allow the heat to escape when you open the lid. Going for a flask that comes in with the push-in or flip function lid makes more sense.
8. Other Features: A perfect thermos flask should have some essential features such as a leak proof lid, BPA free material, anti-skid base, a hanging hook, thermal cover protection, weight, ease of cleaning and maintenance, etc.
9. Warranty: Technology and price competition in a way is good for the consumers. Gone are the times when we used to get warranty only on expensive electric appliances. If you look at the list of 10 best thermos flask in India in 2023, you will see 6 out of 10 thermos flasks comes with a 1-year warranty. Choosing a flask with some warranty or assurance gives more backing to you as a customer.
5 Benefits of a Thermos Flask
1. Portability is one of the biggest benefits that you can get from a thermos flask. In a country like India, where accessibility and availability of clean water can get a bit difficult especially if you are travelling. In these situations, a flask with home water is the most reliable thing to do.
2. Not just winters, if your flask is good and can retain temperatures it can be a very handy gadget in summers especially when you need to consume at least 5-6 litres of water everyday.
3. Because of the way a thermos flask is constructed with no passage of air to pass through, you can be confident that there will be no leakage of beverages from your flask.
4. Buying a bottle of mineral water will cost you around 20 rupees and doing that 3-4 times a day will cost you around 100 rupees a day. Thus, it makes more sense to buy a thermos flask and save money in the long run.
5. If you have a thermos flask, you will most likely reduce the usage of plastic or paper cups which eventually helps to reduce the carbon footprint in the environment.
Borosil vs Milton vs Cello Thermos Flask – Which is Better?
Borosil, Milton and Cello are the best brands for thermos flask in India from a long time, ever since thermos bottles came into the Indian market. However, the main question is which is better amongst Borosil vs Milton vs Cello thermos flask.
Each of these brands are quite popular and we will compare them in terms of their strength, weakness, variety and price to asses which of these thermos flask is the best.
Borosil Thermos Flask
Borosil is an Indian glassware manufacturer which also deals in lunch boxes for office, dining, cookware, etc. One of the main reason you can think of buying a Borosil thermos flask is its affordability. A borosil thermos flask in India can be bought for as low as 600 rupees.
Not just this, there is a plenty of variety for Borosil thermos flasks on Amazon India. The majority of the Borosil flasks are made from stainless steel, and some of their bottles come with a thermal cover too.
In fact, if you are looking for the best flask for hot milk in India, you can consider choosing Borosil since some of their flasks come with a thermos cup too. You can also consider using a Borosil flask for baby milk in addition to water, tea or coffee.
One of the drawback with Borosil flask is that most of their bottles are made in China, which could be a problem with few people, depending on individual’s preference.
Having said this, if you do want to buy the best borosil thermos flask in India, you can go for 1 litre Borosil Stainless Steel Hydra Bolt Trans.
Cello Thermos Flask
Cello is one of the oldest Indian companies that started making its Thermoware for Indian kitchens back in 1986. As of today, Cello deals in almost everything including bottles, teapots, lunch boxes, containers, school, college stationary, etc.
In terms of the price, Cello is quite affordable similar to Borosil, however, some of their thermos flasks are high end and can cost you around 1,500 rupees too. In terms of the quality, Cello sells some of their flasks with cup and a thermos cover including a belt, which is quite useful for portability.
The good thing about Cello thermos flask is it comes in various designs for kids, college going students, office personnel etc. The capacity of Cello thermos flask varies from 500 ml to 1.5 litre. If you are looking for a flask that can keep the water, milk, tea or coffee hot and cold for minimum 15 hours, choose Cello.
Having said this, Cello flasks are not ideal for maintaining temperature retention for more than 24 hours, which is why you can choose Milton over Cello or Borosil. Cello Flip Style Stainless Steel Bottle with Thermal Jacket (1000ml, Silver) is the best Cello thermos bottle in India.
Milton Thermos Flask
Milton by far is one of the best and trusted thermos flask brands in India. I remember buying a thermos flask from Milton back in 2007 when I was in college. The flask was incredibly impressive in maintaining the temperature for more than 24 hours. I used that flask for around 5 years, and I then lost it.
The only problem with that flask was the paint had started to come off after rigorous 3-4 years of usage, but there was no impact on the thermos bottle from the inside. Milton has more varieties of thermos flask as compared to Borosil or Cello and enjoys a better customer experience too.
The good thing is you can consider buying a Milton thermos flask to keep water, milk, tea, coffee, etc hot or cold. It’s a multi-utility thermos flask which also has a thermal cover with a cup in some of their flasks. As far as the price is concerned, you can get a 1 litre flask from Milton for less than 1,000 rupees in India.
Milton offers a 1 year warranty on all their thermos bottles. The only issue with some of Milton flasks is that they can be a bit heavy, especially when they are fully filled with drinks, but this also means, the quality of stainless steel used in the thermos flask is quite impressive.
If you need to buy the best Milton thermos flask available in India, you can choose 1 litre Milton Thermosteel Flip Lid Flask.
The Final Verdict: Borosil vs Milton vs Cello Thermos Flask
As a consumer, if I am looking to purchase the best thermos flask in India, I would look at the price, temperature retention, leakproof design, and finally the customer reviews. Considering all of this, Milton is the best thermos flask brand in India, an edge ahead of Cello and Borosil.
What is the Best Material for a Thermos Flask?
Thermos flask comes mainly in stainless steel material, and not plastic or some other material. Thermos flask made from plastic or glass cannot retain the heat very well as compared to stainless steel.
An important feature for a thermos flask to work is to have a good quality insulation.
Both the Stainless Steel and Plastic bottles have their own pros and cons.
To start with, Plastic as a material is not considered eco-friendly, which is why it is not preferred globally. However, plastic water bottles are lightweight, and they are easy to afford too. When it comes to the recycling of plastic water bottles, it becomes a genuine concern as it can take around 400 – 700 years for a plastic water bottle to decompose.
Additionally, plastic bottles are known to leach chemicals too. This is why, a lot of brands sell their plastic bottles which are free from BPA. If you are looking for a plastic water bottle, you must check the product label and ensure the bottle is made from BPA free plastic. One such bottle is Cello Infuse Plastic Water Bottle with a capacity of 800 ml. Another thing you should know before buying a plastic water bottle is its poor resistance to hot water.
As far as Stainless steel water bottles are concerned, they are totally eco-friendly and safe to consume unlike plastic bottles made from BPA plastic. In terms of age, Steel bottles are the most strongest and can easily live for many years to come. There is no problem with corrosion too as steel bottles are resistant to corrosion.
You can easily use a Steel bottle to keep hot or cold water as they react well to the different temperatures. If you look to buy a Stainless steel bottle, make sure the material is made from 304 grade or 18/8 grade steel. One such example is InstaCuppa Thermos Bottle with a capacity of 1000 ML and 304 grade Stainless steel.
You can also check out our information post on the Types of Water Bottles in India in 2023.
Do’s & Don’ts of a Thermos Flask
1). Always, clean the thermos flask before using it for the first time, this will wash away the odour and any bacteria from the packaging of the flask.
2). Once washed, keep the flask upside down and let it air dry before using it.
3). For effective cleaning, you can use a toothbrush to reach all the nooks and corners of a thermos flask.
4). For a longer life, handwash the flask manually, and don’t use a dishwasher.
5). Avoid filling the thermos flask to the brim, and always leave a bit of space.
6). Don’t use any hard abrasive detergent to clean a thermos flask from the inside.
7). Don’t use a thermos flask to keep beer, whiskey or wine. Rather, buy good quality whiskey decanters, beer glasses or wine glasses for this purpose.
8). Don’t put the thermos flask in the freezer, it won’t do it any good.
How to Clean a Thermos Flask
It is recommended that you wash the thermos flask every day especially in summers. In order to clean the thermos flask effectively, you have a couple of options.
You can either wash and clean the thermos flask with lemon. All you need to do is cut 2-3 lemons and squeeze them in a bottle. Add some boiling water and close the lid to shake it well. Now, open the lid and keep the bottle like this for 6-8 hours post which you can throw the water and lemon skin. By now, you would be able to clean the thermos flask. As a final step, clean the flask with cleaning brush and some lukewarm water and let it dry after that.
The second way of cleaning a thermos flask is with baking soda and some vinegar. Add 1 spoon of baking soda and 1/2 cup of white vinegar in the flask, add some boiling water. Keep the lid open and let it be like this for 30 minutes after which you can throw the mixture away. Use a brush to clean your flask and rinse it thoroughly with some running water. Voila, you now have a clean thermos flask, that’s it.
Are Thermos Flask Dishwasher Safe?
Most of the thermos flasks are made from stainless steel, hence, they are dishwasher compatible. You should also check the product label of the manufacturer, if the thermos flask is safe with dishwasher. Stainless steel thermos flasks can be thrown in the top rack of the dishwasher, but there is a good reason, why these flasks should still be hand washed.
Thermos flasks works on the principle of insulation and when you throw a thermos flask in the dishwasher, the extreme heat and the detergent can impact the insulation of the thermos bottle. Dishwashing a thermos flask can reduce the lifespan of the thermos bottle itself, and hence hand washing is always recommended.
On the other hand, if the thermos flask is made from glass material, it is a strict no for dishwashers.
FAQs
Q. What is the difference between a flask and a thermos?
A. In reality, there is no mechanical or functional difference between a flask and a thermos. Both of these tools are designed to do the same thing. In fact, a thermos is a vacuum flask, which can maintain the temperature of the drinks for longer periods. Whereas, a regular flask may or may not have the temperature retention wall inside the flask itself.
Q. What is the difference between thermos flask vs vacuum flask?
A. There is no difference between a thermos flask and a vacuum flask as a thermos flask itself is a type of vacuum flask. When you add 2 insulated layers, some vacuum and insulation, you get a thermos flask. If you search for the best thermos flask and the best vacuum flask, you will get the same results on Google.
Q. Which is better amongst Milton or Cello thermos flask?
A. Although both Milton and Cello are the best thermos flask brands in India, the difference between Milton vs Cello is not that much. When it comes to the most important aspect which is temperature retention, we observed Milton thermos flask can maintain the temperature for 18-20 hours whereas Cello does it for 18 hours. With the Milton flask, you get a thermal protection cover whereas you don’t get one with Cello. Lastly, Milton offers a 1 year warranty and Cello does not. Keeping all these aspects in mind, Milton is better than Cello.
Q. Which is better amongst Copper vs Stainless Steel thermos flasks?
A. Stainless Steel thermos flasks are more reliable, sturdy and durable. At the same time, copper bottles have a risk of leaching especially if there is any acidic value within the liquids you put in the bottle. While going for a stainless steel flask, make sure it is double walled insulated. Just like copper bottles, steel bottles are not reactive and won’t pick up flavours.
Q. What should I do if my thermos flask is not working or the bottle is leaking?
A. If your thermos flask is not working or the bottle is leaking, this certainly seems to be a manufacturing or a delivery defect. In either of these cases, you should contact the seller and claim your warranty.
Q. How long will the boiling water stay hot in a thermos?
A. Ideally, the thermos flask should keep the water hot for at least 12 hours. If you go for a cheaper model, this duration will be around 6-8 hours.
Q. Which is the best thermos flask for baby milk in India?
A. Milton Thermosteel Flip Lid Flask is the best thermos flask for baby milk in India.
Q. Which is the best thermos flask in India for hot and cold water under 1,000 rupees?
A. If you are looking for the best thermos flask in India for hot and cold water under 1,000 rupees, you can pick anything between Milton Thermosteel Flip Lid Flask and Dubblin Vintage Premium Stainless Steel Double Wall Water Bottle.
Q. Which is the best thermos flask in India for running, cycling and trekking?
A. TRANIAC – Train Like A Maniac Double Walled Vacuum Insulated Stainless Steel Flask with a 1,000 ml capacity, temperature retention of 13/36 hours for hot and cold water, 1 year warranty is the best thermos flask in India for running and trekking.
Q. Can thermos flask keep things cold?
A. A well insulated thermos flask can keep things hot as well as cool for up to 36 hours. The vacuum present in the thermos flask helps to maintain the temperature of the drinks. If you pour a hot tea, it will stay hot and if your pour cold water in the flask, it will stay cold for hours. The duration of the temperature retention depends on the quality of the flask itself.
Q. How thermos flask prevents heat loss?
A. A vacuum or a thermos flask is designed in a way to prevent heat loss, which makes it an amazing flask which can maintain the temperature for longer periods as compared to a regular bottle of water. The heat loss is prevented in the thermos flask by conduction or radiation. Vacuum itself is a bad conductor of heat, the stopper of the thermos flask is tightly sealed, which ensures to prevent any heat loss. Lastly, the inner layer of the flask prevents heat loss by means of radiation. The silver wall of the flask reflects the heat and prevents its loss through radiation.
Q. Can you drink directly from a thermos flask?
A. Yes, you can certainly drink directly from the thermos flask, as long as the lid is opened. Some people prefer to pour the water directly into a cup, rather than drinking from the flask itself. It’s a matter of comfort, if you are comfortable drinking from the flask directly, feel free to do so. However, if you have poured hot tea or coffee in the flask, it may be a good idea to pour the drink in a cup or a glass to prevent any hot spills.
Q. How long do thermos flasks last?
A. A thermos flask can easily last for 5-6 years, depending on how well you maintain it. The only difference might be the outer paint might come off after a bit of rough usage, however, the inner walls of the flask should not be impacted as long as you maintain the thermos flask decently.
Q. What is the difference between a thermos flask and a hydro flask?
A. Both the hydro and thermos flask are made from the same grade of stainless steel, the major difference is price as well as exterior design. Hydro flasks are quite new and expensive in the Indian market, and you might have to pay around 7,000 – 15,000 for a hydro flask in 2023. Hydro flasks will have a proprietary powder coat on the exterior, which makes them pretty good from a grip perspective. If you are a professional hiker or a mountaineer, you can consider buying a hydro flask. For normal day to day activities, a thermos flask is the best choice.
Q. Can you put boiling water in a thermos flask?
A. Yes, you can certainly put boiling water in a thermos flask without any issues. The water will remain hot for long hours, depending on the inner walls and quality of the flask. A thermos flask is made from stainless steel with a double walled interior, hence it is designed to hold boiling or chilled water without an issue.
Q. Why do thermos flask smell?
A. Some thermos flask may have an odour either after packaging when it’s new or after you have poured a drink in it. However, getting rid of that smell is pretty easy, and can be achieved with the help of baking soda. Let the paste of baking soda and some water sit in the flask for some time, after which, you can rinse the bottle and let it air dry. After washing, the smell will go off from the thermos flask.
Q. Can I take an empty thermos flask on a plane?
A. Yes, you can certainly take an empty thermos flask on a plane, in fact, I have done this with various airlines in India and never had a problem with it. However, it is to note that the flask should not have alcoholic beverages in it, as this may go against the airlines policy.
Q. When was the thermos flask invented?
A. The thermos flask was invented in 1892 by Sir James Dewar, which is why, a thermos flask is also known as a Devar flask. Sir James Dewar was a British chemist and physicist at Oxford University, and he became famous for inventing Dewar flask.
Q. Are thermos flasks safe?
A. Stainless steel thermos flasks are totally safe to drink from, considering it is BPA free and does not leach any chemicals into the water or any other drink. At the same time, if the thermos flask is made from glass material, it might have a maximum temperature threshold at which boiling water may shatter or chip the glass. This is why, most of the thermos flasks are made from double walled stainless steel, which is safe.
Q. Are thermos flasks microwaveable safe?
A. Given the fact thermos flasks are made from stainless steel, they are not microwaveable safe. Any cooking vessel or utensil which is made from stainless steel is not microwave safe. Moreover, the point of thermos flask is to keep the drinks at a desired temperature, which is why, you do not need a microwave.
Q. Why thermos flask is silvered?
A. Thermos flasks are silvered due to the simple fact that silver colour is used to prevent heat transfer by means of radiation. The working mechanism of the thermos flask is based on the silver coating which reflects the heat inside the thermos, so that radiation heat transfer cannot take place.
Q. Can I put my thermos flask in the fridge?
A. Yes, you can put a thermos flask in the fridge, however, it does not mean the refrigerator will accelerate the cooling of the drinks inside the thermos flask, due to the vacuum insulation feature present inside the flask.
Q. Can I put ice into the thermos flask?
A. Yes, you can put ice in the thermos flask especially during the Indian summers where the heat is very scorching. The ice cubes will stay intact for a couple of hours, after which they may melt and merge with the drinks.
We hope this post on “Top 10 Best Thermos Flask in India under 1000 Rupees in 2023 – (Best Vacuum Flasks for Water, Milk & Tea)” was useful and informative to you. We also encourage you to read the customer reviews of any product before buying. Should you have any questions on this, feel free to leave a comment. If you want our team to review a product you are interested in buying, you can reach out to us at askus@betterchoices.in, and we will be happy to review it.
