Water Bill Calculator

UK water bills come in two shapes. On a meter you pay for what you use, which means a fixed standing charge, a volumetric rate for every cubic metre that comes out of the tap, and a separate sewerage rate for what goes back down the drain. Without a meter the bill is set by your property's rateable value instead. Water UK puts the average combined water and sewerage bill in England and Wales at £639 for 2026/27, up £33 (5.4%) on the year before. Standing charges typically fall between £100 and £200 a year and volumetric rates between £1.50 and £3.00 per cubic metre, with sewerage costing roughly as much again as the fresh water. Ofwat regulates the companies in England and Wales, while Scottish Water is publicly owned.

Whether a meter saves you money depends on your household size and usage. As a rule of thumb, if the number of bedrooms in your home exceeds the number of occupants, a water meter is likely to save you money, and single occupants in large houses benefit most of all. Someone living alone with no garden to water is paying a household-sized charge for a fraction of a household's consumption. Rateable values rest on a 1990 valuation of the property and bear no relation to what you actually draw, which is why homes built since then are metered as standard.

You have a right to request a free water meter installation. If the plumbing makes fitting one impossible, your supplier may instead offer an assessed charge based on average usage for a household of your size. The decision is not final either, because if the metered bill turns out higher you can revert to rateable value within 24 months. This calculator compares your estimated bill on both metered and unmetered charges, so you can see which option is cheaper for your situation before asking for the meter.

Once you are metered, consumption becomes the lever. A leaking toilet flapper costs £2 to replace and can waste 200 litres a day, so it is the first thing to check. A low-flow showerhead cuts shower use by about 30% and a dual-flush toilet saves 50% on every flush. A bath swallows roughly 100 litres against 35 litres for a short shower. Many water companies give away a water butt for the garden, and running the washing machine and dishwasher only when full stops you paying to move half-empty loads. Together these changes save a typical household £100 to £250 a year.

Help exists for households that cannot simply use less. The WaterSure scheme in England and Wales caps bills for low-income customers with unavoidably high water needs, such as families with three or more children or people with certain medical conditions, and you apply through your own water company. Most companies also run a social tariff giving low-income customers a discount of 50 to 70%, again applied for directly. The Priority Services Register is free and open to vulnerable customers, including elderly and disabled people and families with young children, and it brings advance notice of supply disruptions and alternative water sources when the mains go off.