Best immersion heater

Heating, Cooling & Air Quality

An immersion heater is a useful item for camping and traveling, and it can quickly bring water to a higher temperature in just a few minutes.

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Which immersion heaters are best?

An immersion heater is an electronic heating element that is submerged in water or other liquids to increase the temperature. They come in various sizes for different amounts of water and are particularly useful for travelers, construction workers, farmers and off-grid homeowners and can heat everything from a single cup of water to a large hot tub.

The Gesail 1500W Bucket Water Heater is a powerful model that can bring 5 gallons of water to temperature in a few minutes. It has a stainless steel safety guard and an auto shut-off feature. 

What to know before you buy an immersion heater


There are many circumstances when hot water is required yet access to traditional methods is unavailable. Compact immersion heaters are ideal for travel and can heat small amounts of water at a time for hot drinks or daily hygiene. Larger bucket heaters are more powerful and will heat 5 gallons of water in a few minutes. Some industrial-sized heaters are powerful enough to be used in a hot tub or an outdoor pool.


It stands to reason that the smaller the heating element the less water it can heat. Travel immersion heaters are usually around 6 inches in length and take up little room in a backpack. Bucket heaters are much larger and may incorporate a handle and a clip for holding it in position. 


It is important that an immersion heater be made from corrosion-resistant materials. Aluminum and stainless steel are common choices. Some have titanium heating elements that allow them to be used in chemicals, which may be necessary on farms or construction sites. Additionally, the handle should be insulated to prevent electric shocks, should the heater malfunction.

What to look for in a quality immersion heater

Heat output

Heat output is generally measured in watts. A travel heater usually has a low output and is good for small amounts of water. Travel heaters should also be able to accept both 120- and 240-volt electrical supplies if you want to take them outside of America. If you prefer a more powerful bucket heater, then the higher the output the quicker it will heat the water. An immersion heater with a 1300-watt element will heat a 5-gallon bucket of water in about 10 minutes. 

Safety features  

Since water and electricity can be a dangerous combination, it is vital that an immersion heater has the correct safety features. As a minimum, it should incorporate a safety guard that prevents the heating element from being touched. An auto shut-off will turn the heater off after a specific length of time or when the desired temperature is reached. For true peace of mind, look for a heater with a UL listing to ensure it conforms to current regulations for health and safety.

Optional extras

Depending on how you intend to use an immersion heater, you may opt for one with a thermostat for regulating and maintaining a specific temperature. Some also incorporate digital displays, timers and indicator lights, which offer enhanced control over the functions.

How much you can expect to spend on an immersion heater

A travel immersion heater for a single cup of water is relatively inexpensive and can be found for under $20. For a high-powered heater with a thermostat expect to pay upwards of $50.

Immersion heater FAQ

How much electricity do immersion heaters use?

A. This depends on the output of the heater. A travel heater is usually low-powered and is cheaper than boiling a kettle. A heater with a 1300-watt element will cost around 15-30 cents an hour to run.

Can an immersion heater be left on permanently?

A. If you want to use an immersion heater to warm the water in a pool or hot tub it may be necessary to leave the heater on permanently. If this is the case then you should choose a heater with a thermostat and an auto-shutoff to prevent damage to the element. Additionally, you should never use the heater while you are in the water.

What are the best immersion heaters to buy?

Top immersion heater

Gesail 1500W Bucket Water Heater

Gesail 1500W Bucket Water Heater

What you need to know: This powerful heater will bring 5 gallons of water to 180 Fahrenheit in just a few minutes.

What you’ll love: It is UL listed for safety and incorporates a stainless steel guard to protect the element and has an auto shut off.

What you should consider: This heater doesn’t include a thermostat to adjust the temperature.

Where to buy: Sold by Amazon

Top immersion heater for the money

Lewis N. Clark Portable Immersion Water Heater

Lewis N. Clark Portable Immersion Water Heater

What you need to know: Ideal for travel, this compact heater is designed to heat water for hot drinks and fits inside a regular mug.

What you’ll love: It has a dual voltage system and can be powered using either 120- or 240-volts. It includes a European outlet adapter and a travel pouch.

What you should consider: The power cord is quite short at under 40 inches.

Where to buy: Sold by Amazon

Worth checking out

Pong-Dang Fully Submersible Water Heater

Pong-Dang Fully Submersible Water Heater

What you need to know: This versatile heater has a 1300-watt titanium element and can safely be used in water and chemicals.

What you’ll love: It features a built-in temperature selector and a thermostatic shut-off, meaning it can be left on permanently if necessary.

What you should consider: The heating element is 15 inches long, making it unsuitable for small amounts of water.

Where to buy: Sold by Amazon


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Chris Gillespie writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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