Top 10 list of tankless water heaters in the UK (2025)
The bestseller list compares brands and their tankless water heaters. Which tankless water heater is the best?
- Simple Installation1/2-Inch Water heater connector. In order to install whole house…
- Safety Insurance & Longer LifeOur tankless electric hot water heater 9KW are…
- Saver Energy & SpaceWater is only heated when you need it, not stored in a hot…
- Simple Installation1/2-Inch Water heater connector. In order to install whole house…
- SAFE and DURABLE Applied with multiple protection devices, every piece goes through…
- SMART SELF ADJUSTMENT The hot water heater adjusts power input based on flow rate…
- NOTE: For any instant & tankless water heater, the temperature of water outlet…
- IMPORTANCE for installation: 1. Install vertically to avoid malfunction of the heating…
- Mini water heater designed with compact size, ideal for confined areas, such as kitchens,…
- Safer to use: Instant electric hot water heater have a variety of safety protection…
- 360° Free Installation: The body of the hot water heater is small and does not…
- Easy to operate: The temperature can be adjusted by remote control and touch. Equipped…
- [ Remote Control Convenience ] -- With the included remote control, adjusting the…
- [ Simple to Use and Install ] -- Designed for ease of installation, this unit allows…
- [ Wide Applications ] -- Perfect for various settings, this instant water heater…
- Application Versatility: This water heater is very suitable for applications from…
- Safety and Efficiency: In addition to energy saving and environmental protection,…
- Temperature adjustment: With the water flow, you can freely and easily adjust the…
- Integrated Molded Cast Aluminum Heating ElementThis portable water heater adopts…
- 8-layer Safety ProtectionOur tankless water heater comes with comprehensive safety…
- Multi-function Digital Display & Two Control MethodsThis electric water heater…
- Ideal for Off-Grid Living: No electricity or natural gas required! This instant…
- Enhanced Safety Features: This on-demand hot boiler comes with comprehensive safety…
- Enhanced Safety Features: This on-demand hot boiler comes with comprehensive safety…
- TWO INSTALLATION APPLICATIONS OPTIONAL- Functional for both over sink and under sink…
- EXCEPTIONALLY DURATION- Built in high quality alloy bare heating element, it is corrosion-resistant…
- FLEXIBLE INSTALLATION- When inverting the installation, the numbers automatically…
- Wide ApplicationThis water heater is ideal for applications from cold water to hot…
- Safe and EfficientOur electric water heater has multiple safety protections: anti-leakage…
- LCD Temperature DisplayThis electric water heater is equipped with an LCD screen,…
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The 10 best tankless water heaters to buy in the UK
Finding the best tankless water heater system for your home can help save a lot of money in energy bills, although knowing what to look for in a heating system can be challenging for anyone that isn’t a plumber. Given the cost of paying for a new heating system, you will want to put a lot of thought and consideration into your decision, which is not always easy if you are unfamiliar with what a tankless water heater is and how to choose the right one for your home.
To help with this, we have created a handy buying guide that covers all the information that you need to know to find the best tankless water heaters for your home.
What are tankless water heaters?
As the name suggests, a tankless water heater is a type of water heating system that does not use a large water tank to store heated water. Instead, cold water passes through a pipe and into the heating unit, which uses either a gas burner or electric element to instantly heat the water. Whenever you turn on hot water, you instantly get a constant supply as there is no need to wait for a tank to fill with heated water. Therefore, a good tankless water heater makes hot water very convenient and energy-efficient.
Why should you buy a good tankless water heater?
One of the major benefits of using tankless water heaters is reduced energy consumption. Because there is no tank to fill and store with hot water, it can help to reduce water heating bills. Furthermore, while the initial cost of installation is higher than a tanked water heater, the best tankless water heaters are much more durable so will last significantly longer. This means you can save money over the long term, making it a fantastic investment for many homeowners.
How to choose the right tankless water heater in 2025?
Choosing a new tankless water heater can be daunting for those unfamiliar with water heating systems. So here are some things to consider that can make the process easier:
- Hot Water Consumption: You need to determine how much hot water you consume daily so that you can select a tankless water heater that meets the demand. Simply list all the fixtures in your home that use hot water at any time (e.g. faucet, shower head, dishwasher) and combine their flow rates. To check flow rate, simply refer to the manufacturer instructions for any fixture you’ve bought or check online for a rough estimate of each fixture.
- Temperature Rise: This refers to the temperature that the heater uses to warm incoming water to the desired temperature. To calculate, you need to determine the average temperature of incoming water and subtract from the desired incoming temperature.
- Power Source: A tankless water heater is either gas-powered or electric, so consider which is best for your needs. Electric is suitable for smaller water heaters designed for point of use (e.g. heating water for just the shower), while gas-powered water heaters are best for an entire household’s water heating.
What is the best kind of tankless water heater in the UK?
There are two main types of tankless water heaters available to buy:
- Gas-powered Tankless Water Heaters: Gas-powered systems are more powered and the most used, being the best tankless water heater for an entire household. However, you need to ensure that appropriate piping is in place and consider its location relative to where the heater will go, otherwise extensive installation work may be necessary.
- Electric Tankless Water Heaters: Electrically powered systems are only recommended for point of use rather than a whole household, as it puts too much strain on the electrical supply when forced to heat too much water. It is more affordable to install, however.