Water bills explained: average costs and how to save money

Water is the one household bill where you’ve got zero choice over who supplies you. Your water company is determined by your postcode, full stop. There’s no switching, no comparison sites, no haggling. But understanding how the bill actually works can still help you spot errors or find ways to pay less.

Quick decision tree

• Small household or low usage: check metered pricing first.
• Large household or high usage: compare carefully before switching from unmetered.
• Struggling to pay: check social tariffs and WaterSure before arrears build.

How the billing works

Your water bill pays for two separate things. The water supply side covers treating water to make it drinkable and pumping it to your property. The sewerage side covers taking your used water away, treating it, and disposing of it safely. You pay for both, even though they’re quite different operations. If you happen to have a private septic tank, you may only pay for the supply side.

The split isn’t what you’d expect either. Sewerage actually costs more than the clean water side, roughly 60% of your bill versus 40%. Treating wastewater is expensive. A typical household pays somewhere between £470–600 a year in total, with £220–300 of that being water supply and £250–350 being sewerage, though this varies quite a lot by region.

Most water companies bill either twice a year or monthly by direct debit. Monthly direct debit is easier on the budget and some companies offer a small discount for paying that way. We’d generally recommend it over the twice-yearly option, which has a habit of landing at awkward times.

Metered or unmetered?

This is the big one, because it determines how your bill is calculated.

Unmetered means your bill is based on your property’s rateable value: an old valuation from 1990 that’s tied to your property’s size, type, and location. You pay the same every year regardless of how much water you actually use. The upside is predictability. The downside is that if you’re a light water user, you’re probably overpaying. It’s an outdated system, but it still applies to millions of homes and there isn’t really a way to look up your rateable value easily. It just is what it is on the company’s records.

Metered means you pay for what you use, measured in cubic metres (each one is 1,000 litres). You’ll have a standing charge on top (typically £40–80 a year), but the bulk of the bill comes from your actual consumption. Water rates are usually £1.50–2.50 per cubic metre, sewerage rates £1.50–3.00. The average household uses around 140–150 cubic metres a year.

Which one’s cheaper? If there are fewer people in your home than bedrooms, a meter almost certainly saves money. If you’ve got a big family or water the garden a lot, unmetered is probably better value. We’ve written more about this in our water meters guide.

Who supplies your water?

You don’t get a choice, but for reference, the major water and sewerage companies are: Thames Water (London and Thames Valley), Severn Trent (Midlands), United Utilities (North West), Yorkshire Water (Yorkshire), Anglian Water (East of England), Southern Water (South East coast), South West Water (Devon and Cornwall), Northumbrian Water (North East), Welsh Water/Dwr Cymru (Wales), and Wessex Water (Bristol and Somerset area). Scottish Water covers Scotland and is publicly owned.

In some areas, the company that supplies your clean water and the one handling your sewerage are actually different, which can mean two bills. Your bills will tell you who does what.

Why your neighbour might pay different

Water prices vary a lot across England and Wales because each company sets its own charges (with Ofwat, the regulator, having the final say). Several things drive the differences.

Geography matters, pumping water uphill or across long rural distances costs more. Infrastructure age plays a role too, since some companies are dealing with Victorian-era pipes that need constant maintenance. Where the water actually comes from affects cost (river water needs more treatment than groundwater). And companies currently investing in big projects like new reservoirs or upgraded treatment works pass those costs on to customers.

The result is that someone with Severn Trent might pay £430–470 a year while someone with South West Water could be looking at £650–700 for essentially the same thing. Not much you can do about it, unfortunately.

Getting a water meter

You can request a meter from your supplier and they have to install one for free, provided it’s physically practical at your property. The process is fairly straightforward, you ask, they survey, they install (usually within a few weeks), and you start getting billed on usage.

The important bit: you get a 12-month trial period in England and Wales. If metered billing turns out to cost you more, you can switch back within that first year. After 12 months, the meter’s permanent.

For properties where a meter can’t be fitted (flats with shared supplies, for instance), companies offer assessed charges based on what similar metered homes pay.

Reading your bill

Your bill should break down into a few line items: water supply charge, sewerage charge, a standing charge if you’re metered, surface water drainage (for rainwater running off your roof and drive), and sometimes highway drainage (a contribution towards draining public roads).

If you’re metered, you’ll see a per-cubic-metre rate alongside the standing charge. If you’re unmetered, it’s just the rateable value calculation.

That surface water drainage charge is worth looking at. If your property handles all its own rainwater, maybe you’ve got a soakaway or everything drains into your garden rather than the public sewer, you might not need to be paying it. Contact your company and ask. It’s worth £20–60 a year for some households.

Make sure they’ve got the right details about your property too. If your company is using estimated meter readings, submit your own actual reading, estimates can be way off.

WaterSure: capped bills for certain households

WaterSure is worth knowing about if you’re on a meter and your usage is high for reasons you can’t help. To qualify, you need to be receiving certain benefits (Universal Credit, Income Support, JSA, ESA, Pension Credit, Working Tax Credit, Child Tax Credit, or Housing Benefit) and either have three or more children under 19 at home or a medical condition that means you need extra water.

What it does is cap your bill at the average for your area, even if you use more than that. For families with high water needs, this can save a significant amount, potentially hundreds of pounds a year. You’ll need to reapply each year, but it’s worth the paperwork. We’ve covered the full eligibility criteria in our WaterSure guide.

Bringing the cost down

If you’re on a meter, the most effective things you can do are: take shorter showers (could save £50–100 a year), fix any dripping taps (a single drip can waste thousands of litres over a year), run full loads in the washing machine and dishwasher, and fit a water-efficient shower head. Most water companies will send you one for free.

Check for leaks too. If your bill suddenly jumps for no obvious reason, turn everything off and see if the meter’s still moving. If it is, something’s leaking somewhere. Water companies will sometimes adjust your bill if you can show the leak was hidden and you’ve had it fixed. On a metered supply, an undetected leak can waste thousands of litres and send your bill through the roof.

And if you’re on a low income, it’s really worth checking what support your company offers. Social tariffs can cut bills by 50% or more, and WaterSure can cap them. We’ve covered this in detail in our water bill help guide.

If something goes wrong or you move

Complaining about your bill

If something looks wrong, contact your supplier first and explain the issue. They’ve usually got 10 working days to respond. If that doesn’t resolve it, the Consumer Council for Water (CCW) is the next step, they’re free, independent, and handle around 10,000 complaints a year. Ofwat, the regulator, is the last resort but rarely gets involved in individual billing disputes.

One thing worth knowing: water companies cannot disconnect your supply for non-payment. Unlike energy companies, they legally can’t cut off your water. That’s one small mercy. But they can still add debt collection costs and report you to credit reference agencies, so it’s better to get ahead of any problems early.

Moving house

Tell your supplier your move date. If you’re on a meter, take a final reading. They’ll send a closing bill for the old place. At the new address, you’ll need to contact whoever supplies that area (it might be a different company) and set up a new account. Check what band your new property falls in too, it might be quite different from what you’re used to, especially if you’re moving between regions with different water companies.