A body representing the customers of water companies said complaints had risen by almost a third because concerns were not being addressed.
The Consumer Council for Water (CCW) said it had handled 7,977 complaints in the past year from people who had “exhausted” their company’s complaint process.
It found Thames Water to be the worst performer, with Yorkshire Water and Cambridge Water also poor.
All three water companies said they were working with CCW to make changes.
Just under 223,000 complaints were made to water companies in England and Wales during 2023-24 – a rise of 29%, CWW figures revealed.
Billing disputes made up more than half of complaints, and concerns about environmental performance, such as spills from storm overflows and pollution, increased by 217%. Complaints about water meters also rose.
CCW chief executive Dr Mike Keil said households were having to waste far too much time and energy resolving complaints, which water companies “should be getting right first time”.
“We’re particularly concerned to see a significant rise in complaints from customers with water meters who are questioning the accuracy of their bill,” he said.
“More companies are planning to roll out smart meters over the next few years, so they must listen and act on people’s concerns now or risk further damaging customer trust.”
CCW also assessed how well complaints were handled, with Thames Water, Yorkshire Water and Cambridge Water rated as poor.
Wessex Water and Portsmouth Water received top marks.
Thames Water’s retail director David Bird said the company had an “ambitious business plan” based on customer feedback and insight.
“CCW has recognized the collaborative approach we have taken and that the improvements we are making are showing promise,” he said.
“However, we recognize we have more to do.”
He said customers had told the company to focus on delivering safe and resilient water supplies, address concerns over overall performance – including on customer service – and to deal more effectively with wastewater.
‘Fallen short’
Cambridge Water said it was disappointed its customer service levels had “fallen short”.
Between 2023 and 2024, it said it had received about 1,200 complaints – less than 1% of its customers.
It added that it had “taken on board” the key comments from the report and would be working closely with CWW to address the issues raised.
Yorkshire Water said it was continuing to invest in new systems and training for its customer experience teams.
Imran Patel, its group customer experience director, said: “We have worked closely with CCW to audit our complaints process and have received positive feedback for our customer-focused culture and the speed and effectiveness of complaints resolution.”
Water UK, the trade association for the water industry, said companies were working hard to provide drinking water that was “independently rated the joint-highest standard in the world”.
It said a rise in customer complaints should be examined, but that not all were necessarily evidence of poor service.
“A better measure is the number of complaints sent by the Consumer Council for Water to adjudication, which fell 63%, from 153 late last year to 57 for the equivalent period this year,” it said.
It added firms were also being affected by funding cuts from water regulator Ofwat, which needed to “enable companies to provide [customers] with the service they rightly expect”.
Water companies have put forward plans for bill increases, although Ofwat has made proposals to cap them. It is due to make a final decision in December.
Ofwat said it had also seen customer satisfaction fall across water companies.
A spokesperson said, while it was challenging companies to invest in their networks, this alone would not solve the problem.
“We have recently introduced a new customer focused license condition, as well as new vulnerability guidance, to raise the levels of customer service to the standard we expect across the sector,” they added.