A thermos flask also referred to as a vacuum flask or a dewar flask is an insulating bottle that helps in maintain the temperature of the drink. The best ones do it for the longest period of time.
A thermos flask lets you enjoy your favorite drink at the desired temperature. It is very helpful when you are out on a trek or on a long drive. The best part about it is you can carry it anywhere along with you.
Before buying a thermos flask, here are some factors that you should consider:
Capacity:Â
Thermos flasks offer different storage capacities. It ranges from 350ml to 1000 ml. You can select the storage capacity as per your requirement.
Heat Retention:
The heat retention refers to the amount of time that a flask can keep the water hot. While some flasks offer a retention rate of 4-5 hours, few offer 12-24 hours too.
Material:
There are many materials that offer good thermal insulation. Amongst all, the double-walled stainless steel is considered the best. Steel is durable, corrosion-resistant, and scratch-resistant.
Some other factors that need to be considered are design, delivery system, etc. To make sure you buy the best thermos flask, we would advise you to take a look at our comprehensive Buying Guide mentioned below.Â
After an extensive research and testing many products, we have shortlisted 7 best thermos flasks that are available in the market. Let’s have a look!
Best Insulated Flask Bottles in India
| Products | Max capacity | Material used | Warranty | Buy Now |
|---|---|---|---|---|
| Milton Vacuum Flask | 1000 ml | High-quality stainless steel | 1 year | CHECK ON AMAZON |
| Milton Vacuum Flask | 1000 ml | Stainless steel coated with copper | 1 year | CHECK ON AMAZON |
| Instacuppa Vacuum Flask | 1000 ml | Matte exterior finishing and stainless steel | 1 year | CHECK ON AMAZON |
| Amazon Brand Flask | 1000 ml | High quality stainless steel | N.A | CHECK ON AMAZON |
| Borosil Vacuum Flask | 500 ml | High quality stainless steel | 1 year | CHECK ON AMAZON |
| CROCKERIVacuum Flask | 500 ml | stainless steel | N.A | CHECK ON AMAZON |
| QUICK SHEL Vacuum Flask | 450 ml | High quality 304 stainless steel | N.A | CHECK ON AMAZON |
Best Insulated Flask Bottles Reviews in India 2021
1. Milton Vacuum Flask
This insulated vacuum flask water bottle is ideal for those who are looking to buy it for daily use or travel purposes as its high-quality sleek and slender design makes it long-lasting, eco-friendly and very easy-to-use. We have put it first in our list because if offers everything that you would be looking for:
Maximum capacity: 1000 millimeters
Other best features of Milton Thermosteel Duo Deluxe are
- Lightweight: it is 513 g before filling which is very light to be carried
- Material used: High-quality stainless steel with inner and outer body covering
- Comes with double: walled vacuum insulator and a simple threaded lid for easy use
- Dimensions: 33 X 8cms which can easily fit inside shoulder, school or trekking bag
Warranty: 1-year warranty on the product
Pros
- Ideal for travel and daily use
- Easy to clean
- Sturdy construction
- Can keep the cool or hot liquid for 12 hours and more
- Comes in different colors
- Sweat free non-slip grip
- BPA free
- Leak-proof
- Condensation-free exterior
Cons
- Can retain for 12 hours only
2. Milton Vacuum Flask

Maximum capacity: 1000 millimeters
Other notable features of Milton Thermosteel Flip Lid are
- Lightweight- 699g, which can be easily carried anywhere
- Material used- Stainless steel and it is coated with copper for better heat retention
- Comes with double-walled vacuum insulator and a unique flip lid for better retention and easy pouring
- It occupies less space and hence very portable
Warranty: 1-year warranty on manufacturing defects
Pros
- Can keep the cool liquid for 24 and hot for 12 hours
- Non-stick grip
- Rust-free
- Leak-proof
- BPA free
- Easy to clean and maintain
- condensation-free exterior
Cons
- Flip lid
- Heavier than other insulated flasks
3. Instacuppa Vacuum Flask

Maximum capacity: 1000 millimeters
Other salient features of Instacuppa Thermos Bottle are
- Lightweight- it is around 450 g which enables a person to only carry the weight of water or beverage
- Material used- Matte exterior finishing and food-grade 304 stainless steel
- Comes with a screw-on lid which is most popular during gymming
- Can easily fit inside the car cup holder, shoulder, school or trekking bag
Warranty: 1-year warranty on manufacturing defects
Pros
- Ultra-modern design
- Can keep the cool liquid for 24 and hot for 12 hours
- Non-stick grip
- Rust-free
- Leak-proof
- BPA free
- Easy to clean and maintain
- Condensation-free exterior
Cons
- Heavier than other bottles
4. Amazon Brand – Solimo Double Walled Insulated Stainless Steel Flask
If you are someone who drinks hot water all day long or can’t stay without sipping a cup of coffee or tea during a trip, you must go for this flask from Solimo. It comes in a modern design with matte finish, making it look elegant.
Maximum capacity: 1 litre.
Other notable features of Solimo flask:
- Double-walled insulation: With the two steel walls and vacuum in between, this bottle can keep the contents inside hot or cold for as long as 9 to 10 hours.
- Material: The entire body of the flask is made of food-grade stainless steel and the lid contains BPA-free plastic to ensure no chemicals leach into the liquids inside.
- Weight: As it is entirely made of steel, it weighs 495 grams, so it is not tough to carry it anywhere you go.
- Size: Measuring 32.08 x 9.03 x 32.08 cm, this flask is compact enough to fit into the cup holder of your car.Â
Pros
- Can keep beverages hot or cold for up to 10 hours.
- Rust-free.
- Leak Proof lid.
- Doesn’t leave any sweat on the surface of the bottle.
- Wide mouth opening for easy cleaning.
Cons
- No warranty from the brand.
5. Borosil Vacuum Flask

Maximum capacity: It can easily suffice a single person as it comes with a capacity of 500 millimeters
Other salient features of Borosil stainless steel Hydra trek are
- Lightweight- you can carry it anywhere as it is approx 250 g
- Material used- Your bottle can be used for a longer duration as it is equipped with 304-grade stainless steel
- Comes with a wide mouth and drip-free slipping
- You can use it for multiple purposes that is carrying at the office, home or gym.
Warranty: 1-year warranty on manufacturing, you will not have to spend a single penny if there is any manufacturing defect.
Pros
- Condensation free-exterior
- BPA and Phthalate free
- Rust-free
- Leak-proof
- Easy to clean and maintain
- Very lightweight
Cons
- Only 500 millimeters water capacity
6. CROCKERI Stainless Steel Thermos Flask Bottle
If you are looking for a stylish flask that suits almost every purpose like gym, school, college or office, then this CROCKERI bottle is an ideal investment. Apart from its modern looks, it also has a temperature display on the lid, so you know how long the liquids stay hot or cold.Â
Maximum capacity: 500 ml
Other notable features of CROCKERI Flask Bottle:
- Drip-free sipping: Having a round cup mouth and a silicone seal, the bottle allows you to sip with more comfort. There’s also a stainless steel strainer that prevents the pulp from the juice while drinking.Â
- Vacuum insulation: With the stainless steel and copper layers, and a vacuum in between, the liquids inside the flask stay cold for 12 hours and hot for 8 hours.Â
- Size: Measuring 20 x 15 x 5 cm and weighing just 400 grams, the bottle easily fits inside your backpacks, cup holders and gym bags. Also, the wide mouth opening allows you to pour ice cubes inside the flask to keep your favourite beverages cold for 24 hours.
- Material: The flask is made of two layers of 304-grade stainless steel with copper plating to preserve the temperature for long. Moreover, there’s a special matte exterior to provide the right grip for you to hold it.Â
Pros
- Contemporary design.
- Lightweight.
- Temperature display on the lid.
- Matte exterior for grip.
- Keeps beverages hot or cold for up to 12 hours.
Cons
- No warranty from the brand.
7. QUICK SHEL Vacuum Flask

Maximum capacity: 450 millimeters
Other best features of Quick Shel BPA-free are
- Lightweight- across 350g which is lighter than any other flask
- Material used- High-quality 304 stainless steel
- Comes with twist-on lid and a wide mouth so you will not have to worry about anything
- Can be easily carried anywhere gym, office or for traveling purposes
Pros
- Non-stick grip
- Rust-free
- Leak-proof
- BPA free
- Easy to clean and maintain
- Very lightweight
- Condensation-free exterior
Cons
- Can keep the cool liquid for 6 hours only
- No warranty
Conclusion
While there are varied ranges of insulated flask bottles available in the market which are responsible for keeping the liquid cool or hot for many hours, we find Milton Vacuum Flask to be the best fit as it comes with a sleek and slender design, very easy to use, easy to carry, easy to clean, lightweight, ideal for travel and daily use, leak-proof, has the capacity to store 1 liters of water or liquid, BPA free and eco-friendly.


