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By only using the water you need, and not overfilling a kettle, you can save yourself time, money and energy.

The Energy Saving Trust say that the average household could save £11 a year in energy bills by only filling the kettle as much as needed*. This might not sound much on its own, but with other energy-saving changes it all adds up.

Take the time to learn how much water is required for drinks or dishes you make regularly.

For a cup of tea, between 150ml and 250ml should be enough depending on the size of your mug.

Different foods require different amounts of water – so check the packet before cooking to plan ahead and avoid overfilling your kettle.

Although filling up a kettle can be something of a habit, it is worth making a change. This easy-to-follow change can add up to savings over the course of a year. What’s more, it will save you time as your kettle will boil faster with the correct amount of water in it.

You might find that you can’t see where the fill line is from the outside of the kettle. If that’s the case, use a small measuring cup or jug next to the kettle to help you boil only what you need.

Illustration shows lightning bolt and wording which reads make a plan, stay warm, save energy.

Only boil the water you need

Our Green Doctors have identified helpful impartial advice on what can really make a difference in reducing bills and saving energy.

Download our supporting home resources – our action plan, our meal and shopping planners, and our stickers – to help you make changes which stick.

Make a plan. Stay warm. Save energy.

  • Place one of our stickers on the kettle to remind you.
  • Identify a mug or jug to use for measuring out the amount of water you need to make a cup of tea or coffee. That way you’ll only boil the water you’ll use.

*Savings based on a typical three-bedroom semi-detached gas heated house, with an 88% efficient gas boiler and average gas tariff of 6.9p/kWh and electricity tariff of 27.4p/kWh. Emission savings include all scopes and greenhouse gases expressed as carbon dioxide equivalent. Correct as of October 2023.

Groundwork logo, Green Doctor programme logo, and supported by the Cadent Foundation logo.

Only boil the water you need