Household Complaints Report 2025-26
CCW has published its annual household complaints report for 2025-26, which examines complaints made directly to water companies and those brought to CCW.
The report reveals that complaints rose at an unprecedented rate against a backdrop of substantial bill increases, with the industry average bill rising by 26%.
Key findings
- Complaints brought to CCW rose by 84%, from 8,235 in 2024-25 to 15,115 in 2025-26. This was the steepest increase in household complaints CCW has recorded in its 20-year history.
- Overall complaints made directly to water companies increased by 56%, from 205,853 to 321,347.
- Bills continued to dominate customers’ concerns, with complaints about billing increasing by 72% to water companies and almost doubling (97%) among the cases brought to CCW.
- Complaints about the scale of the bill increases rose by 54%, while complaints from consumers saying their bills had become unaffordable rose by 129%.
- The figures suggest many households were looking for ways to manage rising costs, with complaints to CCW from customers who were unable to have a water meter installed increasing by 464%.
- Complaints about debt recovery action increased by 49%.
- Thames Water and South West Water were the poorest-performing water and sewerage companies.
- Portsmouth Water and Bristol Water were the best-performing companies.
Appendices
Normalising complaint volumes
To allow meaningful comparisons between companies of different sizes, we calculate complaint rates relative to the number of water and wastewater connections served by each company. Complaint volumes are presented as the number of complaints per 10,000 connections.
The calculation is: total complaints ÷ total connections × 10,000
For example, company A:
- total complaints: 600
- total connections: 4,000,000
- complaints per 10,000 connections: 600 ÷ 4,000,000 × 10,000 = 1.5
Comparing company performance
Where we compare the performance of individual companies we do so within their respective segments as either Water and Sewerage Companies (WaSCs) or Water Only Companies (WOCs).
This recognises the differences between the two company segments and ensures that the quartile boundaries are calculated separately for each group.
Performance measures
We assess company complaint performance using two measures:
- Volume of complaints (Total complaints per 10,000 connections)
- Complaint-effort score
Together, these measures are intended to reflect both the underlying service received by customers and the effort a customer has to put in to get their complaint resolved to their satisfaction.
Volume of complaints
We use total complaints per 10,000 connections to measure complaint volumes.
To compare companies fairly, WaSCs and WOCs are assessed separately. Quartile boundaries are calculated for each group using the complaints per 10,000 connections data for all companies in that group.
Companies are then grouped into four quartiles based on their complaint rate, with Quartile 1 (Q1) representing the best performance and Quartile 4 (Q4) the poorest performance. Companies are then assigned a performance colour ranking as follows:
| Quartile | Colour ranking | Description |
|---|---|---|
| Quartile 1 | Good | Lowest complaint rates in the group (below Q1 value) |
| Quartile 2 | Moderate | Better than the median* (Q1 value and below Q2 value) |
| Quartile 3 | Weak | At or higher than the median* (Q2 value and below Q3 value) |
| Quartile 4 | Poor | Highest complaint rates in the group (Q3 value and above) |
*Median - The median is the middle complaint rate for the group when all companies are ranked from the lowest complaint rate to the highest complaint rate.
Complaint-effort score
The complaint-effort score is a composite measure based on:
- stage 2 complaints per 10,000 connections, representing complaints escalated to the second stage of a company’s complaints process; and
- complaints to CCW per 10,000 connections
Both components are based on the quartile performance within WaSC and WOC groups where Quartile 1 is the best performing quartile. Each quartile is then scored as follows.
| Quartile | Score |
|---|---|
| Quartile 1 | 1 |
| Quartile 2 | 2 |
| Quartile 3 | 3 |
| Quartile 4 | 4 |
The scores for Stage 2 complaints and complaints to CCW are then added together to produce an overall complaint-effort score for each company. The resulting score is used to assign a complaint-effort ranking as follows:
| Complaint-effort score | Complaint-effort ranking |
|---|---|
| 2 | Good |
| 3-4 | Moderate |
| 5-6 | Weak |
| 7-8 | Poor |
For example:
| Company | Stage 2 complaints per 10k connections | Quartile score | CCW complaints per 10k connections | Quartile score | Complaint-effort score | Complaint-effort ranking |
|---|---|---|---|---|---|---|
| Company A | 1.2 | 1 | 1.5 | 1 | 2 | Good |
| Company B | 2.8 | 2 | 3.1 | 2 | 4 | Moderate |
| Company C | 4.5 | 3 | 5.0 | 3 | 6 | Weak |
| Company D | 6.2 | 4 | 7.3 | 4 | 8 | Poor |
The composite score is calculated by adding together the quartile scores:
- company A: 1 + 1 = 2 (Good)
- company B: 2 + 2 = 4 (Moderate)
- company C: 3 + 3 = 6 (Weak)
- company D: 4 + 4 = 8 (Poor)
A lower composite score indicates better performance, while a higher composite score indicates poorer performance.
