Check the calculation first: readings, tariff, wastewater basis, support, and rebates.
Start with bill factsMoney and accountability
Follow the bill money without oversimplifying it.
Water bills pay for water, wastewater, service, infrastructure, financing, and support schemes. The hard question is whether customers are getting the promised service, investment, and transparency in return.
Current money picture
Bills are rising while regulators are tightening scrutiny.
GBP 104bn
sector upgrade approved by Ofwat for 2025-30 in PR24.
Source: Ofwat PR24 final determinations, 2025-30 period
36%
average 2029-30 household bill rise before inflation in Ofwat's final determinations.
Source: Ofwat PR24 final determinations, bill impact figure
GBP 645m
dividends declared by water companies in 2024-25, down from GBP 1bn in 2023-24.
Source: Ofwat financial resilience report 2024-25
9.3%
of current households were reported in arrears in Ofwat's 2024-25 performance report.
Source: Ofwat performance report 2024-25Simple view
Keep the money story in three parts.
Use PR24 and performance reports for sector context, not as proof of an individual error.
Open source linksUse dividends, redress, arrears, complaints, and marketing rulings as careful context.
Build the complaintBill anatomy
What a household bill can include.
Not every home has every line. Water-only areas may receive wastewater services from a different company.
Clean water
Abstraction, treatment, pipes, pumping, storage, mains repairs, water quality testing, and customer supply.
Sewerage
Sewers, pumping stations, sewage treatment, permits, sludge handling, storm overflow work, and environmental schemes.
Standing and usage
Metered bills usually combine fixed charges and use-based charges. Unmetered bills normally use rateable value.
Debt and equity return
Ofwat says customers pay reasonable investment costs over time. Companies raise debt and equity upfront to fund assets.
Social tariffs
Ofwat reports social tariffs support 6% of household customers across England and Wales; cross-subsidy levels vary by company.
Rewards and penalties
Outcome delivery incentives can reduce or increase future bills depending on company performance against regulated targets.
Ask better questions
The question is not just "profit or no profit".
Was the charge calculated correctly?
Ask for readings, tariff, wastewater assumptions, surface-water basis, standing charge, meter serial number, and any estimated element.
Was promised investment delivered?
Ofwat says funding not spent on required investment can be subject to clawback mechanisms and returned through lower bills.
Was performance poor enough to trigger bill reductions?
Ofwat says underperformance payments returned more than GBP 700m to customers across 2020-25 and more than GBP 260m in the last year.
Was marketing missing material context?
ASA rulings against Anglian Water and Wessex Water show environmental adverts can be misleading if they omit relevant environmental-impact context.
Dividends and debt
Dividends are regulated, but not banned by default.
Ofwat says it does not set dividends, but company boards must take account of service for customers and the environment, investment needs, and financial resilience. From 1 April 2025, earlier cash lock-up rules can restrict certain payments, including dividends, where financial resilience is at risk.
Show careful percentages and caveats
Percentages
Quote percentages only when the source defines the denominator.
Avoid fake pie charts and loose percentages. Some percentages are safe to quote because Ofwat defines exactly what they measure.
| Measure | Current source figure | What it means |
|---|---|---|
| Average bill increase | 36% by 2029-30 before inflation | Ofwat PR24 sector-average household bill change versus 2024-25, not a guarantee for a specific home. |
| Social tariff cross-subsidy | 3% of the household national average bill | Ofwat's sector average contribution funding support equivalent to 55% of the national average bill for supported customers. |
| Bioresources share | 9% to 17% of wholesale wastewater bill | Ofwat's 2025-30 company range for sludge/bioresources as a share of wholesale wastewater bills, not the total household bill. |
| Regulated asset growth | 32% real-terms RCV growth over 2025-30 | Ofwat financial resilience context for investment and financing need, not a direct household-bill percentage. |
Show enforcement and advertising examples
Accountability examples
Cases to describe carefully.
These are examples of regulatory or advertising findings. They do not prove any one household bill is wrong.
Thames Water: nearly GBP 123m
Ofwat announced penalties following wastewater and dividend investigations.
Yorkshire Water: GBP 40m package
Enforcement package following Ofwat's wastewater investigation.
Dwr Cymru: performance data
Ofwat's final decision covered misreporting of leakage and per capita consumption performance data and customer redress.
Wessex Water advert
ASA upheld a complaint that environmental claims omitted material information.
Anglian Water advert
ASA upheld complaints about environmental advertising that omitted material information.
Bonus rule
Ofwat said more than GBP 4m of potential bonuses were blocked in the first year of the new PRP rule.
Money source links
Ofwat PR24 final determinations
Ofwat returns and dividends
Ofwat financial resilience 2024-25
Ofwat bioresources bill share
CMA disputed price controls 2026
Ofwat performance 2024-25
CCW Water Matters 2026
Use the linked original sources before relying on financial figures.