'Why won't my water company be straight with me?': Confusing bills hide the price hikes

Is your water bill increasing and you don't know why? You're not alone.

Ellie Simmonds discusses the frustrating reality of being a Thames Water customer, as her bill jumps staggeringly despite only a 10% increase in usage.

This column appears in the September issue of Which? Magazine. Join Which? to get our monthly magazine, or if you're already a Which? member, add the magazine to your membership in your online account or by calling us on 029 2267 0000.

Ellie's experience with confusing bills

Ellie Simmonds, Which? senior researcher and writer, says:

'Along with 16 million other people, I’m a hostage – sorry, I mean customer – of Thames Water. I don’t have a choice over who supplies my water, so it doesn’t need to woo me to stay. 

But I would like it to be straight with me. The first page of my most recent bill proclaimed that it was changing my payments to £107. It didn’t say what my current payment was. Or how frequently this £107 would be charged. ‘Maybe it’s yearly’, suggested my ever-hopeful husband.

‘You don’t need to do anything’, the bill told me. But in reality, I probably do – like ask for a pay rise or extend our mortgage, so I can afford to pay it.

It felt like the next part of the bill lectured me on my water use. I’m using 10% more, apparently. When I began reading the third page, the penny dropped. My water use isn’t the story.

Hidden in a dazzling array of figures was the new rate per cubic metre. For freshwater, it’s up 29%. For wastewater, up 35% (I worked that out myself, it wasn’t spelled out). Fixed charges are also up 98% and 40%, respectively. My apparent 10% increase in use pales by comparison.

My monthly bill jumped from £65 to £107 – something that’s only mentioned on page four of my bill. That’s a 65% rise and it has very little, if anything, to do with increased use. 

Thames Water has a £18bn debt, a history of paying execs big bonuses (now thankfully ‘paused’), and a shocking record of pollution and leaks.

Now Ofwat, economic regulator for the water industry in England and Wales, will be scrapped in favour of a watchdog setup to ‘prevent past abuses’.

Don’t take us for fools. Fewer cups of tea or a couple of shorter showers isn’t going to significantly reduce my bill.

Thames Water told us that it aims to make bills clear. It added that it includes analysis of customers’ water usage to help them make decisions on their water use and is using extra funding raised for investment.'

Water bill price hikes came into effect across the UK in April 2025 - head to our guide for advice on managing your bills.

If you're struggling to pay your bills

Head to Citizens Advice to weigh up your options – you might be able to get help if you have no or low income, or if you're on benefits.

It's also worth calling your supplier to see if you can make payment arrangements that suit you better.

If it's your energy bills you're worried about, see our advice: Help if you're struggling to pay your energy bills.

Adapted for online publication by Natalie Turner, original article published in Which? Magazine, September 2025.