Millions of water and sewerage bill payers could get payouts if new legal claims succeed – here's what you need to know

Six water firms – Anglian Water, Northumbrian Water, Severn Trent Water, Thames Water, United Utilities and Yorkshire Water – could be taken to court for allegedly misleading regulators over their handling of wastewater.

The legal claims allege that water firms misled authorities over the number of spills and amount of sewage they've released  

The water firms in question are being accused of breaking competition law by not properly reporting the number of spills and discharges of sewage made into waterways, such as rivers and lakes. 

This is important because the number of pollution incidents a water company reports to regulators is a key factor in determining how much that firm can charge consumers for its services – and the claims argue that consumers have been overcharged as a result of underreporting. 

Law firm Leigh Day and Professor Carolyn Roberts, an environmental and water consultant, are bringing the claims on behalf of 20 million affected customers.

It's possible that similar claims could arise against other water firms in the future, though Leigh Day told us it was focusing on the six largest firms in England for the time being.

Even if the claims succeed, payouts won't be huge

The claims are aiming to recoup compensation payments of over £800 million in total, so you could be due a payout if they succeed. However, the amount you could get will vary depending on your water firm:

• Anglian Water customers could receive up to £14.45.

• Northumbrian Water customers could receive up to £109.38. 

• Severn Trent customers could receive up to £39.71.

• United Utilities customers could receive up to £66.98.

• Yorkshire Water customers could receive up to £101.59.

As the claim against Thames Water is still being compiled, there's no estimate yet about how much its customers could get. Leigh Day told us it should be able to provide more details "in the coming months" – we'll update this story when we know more.

You don't need to do anything to be included in these legal claims

The exact definition of who could be included in the claims will be determined during the legal process, if it goes ahead. But you're likely to qualify if you've paid a water bill to at least one of the accused water firms since 1 April 2017 for Severn Trent Water and since 1 April 2020 for the rest. 

If you are eligible, you don't need to opt in (there will be an option to opt out) and there's no action to take at this stage. If the claims are successful and there is compensation to be paid, you may be required to come forward to claim your share. 

You can register for case updates from the team behind the claims, which will include when you're able to opt out and if you may need to come forward to claim any compensation.

You won't incur any costs for taking part 

You won't need to pay anything in order to take part and Leigh Day has confirmed that none of the payout amounts above will be subject to any lawyer fees or deductions if the claims win.

If the claims are unsuccessful, you won't be liable for any legal costs as any liability would fall on the person bringing the cases, in this instance Professor Roberts. Professor Roberts has taken out specialist insurance to cover the cost of any legal fees should the claims be unsuccessful. 

It's still very early days

So far, five of the six claims have been filed with the Competition Appeal Tribunal (the exception is the claim against Thames Water, which is expected to be issued in the new year). 

The Tribunal will now decide whether the claims can go ahead. Even if the group claims get the green light, it'll still take a long time for them to proceed through the legal system. Leigh Day estimates it could take several years for the claims to reach a conclusion. 

While you can't switch your water provider, there are still ways to make savings. See our Cut your water bills guide for more on this.