Complaints escalated to the Consumer Council for Water (CCW) by business customers surged by almost a third, according to the watchdog's annual Business Customer Complaints Report. Billing remains the biggest source of complaints, accounting for 90% of cases escalated to CCW.

The 30% increase meant complaints to CCW from business customers about their water retailer rose from 1,966 to 2,562 in 2025/26 - reversing the positive progress seen in the previous year, when complaints to the consumer watchdog from businesses fell by 14%. Billing remains the biggest source of complaints, accounting for 90% of cases escalated to CCW.

Retailer performance remains mixed, with ADSM, Water2Business, Source for Business and Hafren Dyfrdwy among the top performers, while SES Business Water, Clear Business Water, Castle Water and Water Plus rank among the poorest performers.

Despite the rise in disputes brought to CCW, the overall number of complaints made directly to water retailers remaining largely unchanged, rising by just 0.7% to 20,139. But more of these complaints were not resolved at the first opportunity, with a 15% increase in those reaching the second stage of retailers’ complaints process.

Issues related to billing continued to cause the biggest headache for business customers, making up almost half (48%) of complaints made to retailers and 90% of those escalated to CCW. In particular, measured billing – where charges are based on the amount of water measured through a meter – remains the single biggest driver of complaints to CCW, accounting for over half (54%) of all billing cases.

CCW said improving the accuracy and clarity of bills will be crucial if these complaints are to fall. The continuing rollout of around 800,000 smart water meters for business customers over the next five years has the potential to reduce disputes of this kind by giving retailers and customers better access to data on water consumption.

However, recent research by CCW found retailers are not communicating effectively enough with businesses about smart meter installations and their benefits. This risks smart meters becoming a growing cause of complaint, rather than part of the solution.

Mike Keil, Chief Executive of CCW, said:

“Business customers should not have to waste precious time and energy exhausting the complaints process to get their dispute resolved. Some water retailers need to get more things right first time for customers and provide the high standards of service the water market in England was supposed to deliver.

“There remains far too much inconsistency in performance across the retail water market and the gap between the best and worst performers needs to close. CCW will continue to work with retailers to improve their complaint handling and we’ll use our company assessments to drive up customer service levels.”

The report also highlights growing concerns around debt, with complaints to CCW rising by 131% during 2025-26. This reflects the financial pressures many businesses are facing as they continue to grapple with higher water bills, highlighting the need for retailers to provide stronger support for customers struggling to manage their payments.

In 2025, the water watchdog supported household and business customers with more than 16,000 complaints which they had been unable to resolve directly with their water company and/or retailer. During 2024-25, CCW helped to secure more than £1.3 million in financial redress for aggrieved customers. 

Click here to download the report