Most water bills get read once and then filed. Below is a typical quarterly business water bill for a small café, followed by what each line is and how it's worked out.

The specimen

Figures are illustrative. Rates vary by region and by wholesaler.

  • Meter reading: previous 04512 (A), current 04572 (E). That's 60 m³ used.
  • Water standing charge: 20mm meter, 91 days. £10.00
  • Water volumetric: 60 m³ at £1.60. £96.00
  • Wastewater standing charge: 20mm meter, 91 days. £35.00
  • Wastewater volumetric: 57 m³ (95% of 60) at £1.90. £108.30
  • Surface water drainage: Band 2. £40.00
  • Highway drainage: Band 2. £12.00
  • VAT: 0%. £0.00
  • Total: £301.30

Wastewater and drainage make up about 65% of this bill.

The meter reading

The letter after each reading shows where it came from. "A" is an actual reading taken from the meter. "E" is an estimate, calculated from your past usage. In this bill the current reading is estimated, so the 60 m³ is a projection, not a measurement.

Since Ofwat lifted its restriction in 2021, customers can also submit their own readings to the central market system, which replaces an estimate with an actual figure on the next bill.

Water and standing charges

The volumetric charge is cubic metres used multiplied by your rate. One cubic metre is 1,000 litres.

The standing charge is a fixed fee for being connected. It's set by the size of your meter, not by how much you use, which is why a 20mm meter costs less than a 40mm one even if both sit idle. Changing meter size is a wholesaler decision and usually involves a site visit.

Rates are reset every April. For 2026/27, Thames Water's published maximum wholesale bill increase for water-only non-household customers was 11.7%, after adjustments.

Wastewater

Wastewater is usually the largest part of the bill, and it costs more per cubic metre than clean water. It's also billed on an assumption rather than a measurement: that 95% of the water drawn from the mains returns to the sewer. Wholesalers such as Northumbrian Water and Veolia state this figure in their charging documents. The other 5% is the allowance for water that never comes back.

A café sits close to that average. Businesses where water ends up in a product, evaporates or goes on plants sit well below it, which is what the non-return to sewer allowance exists for. Our audit guide explains who qualifies.

Highway drainage

This is each customer's contribution to the cost of draining public roads and footpaths. It's charged in bands, like surface water drainage, but the two are separate: a site can have its surface water charge removed and still pay highway drainage. Ofwat's own guidance treats it as a cost water companies recover from all customers.

Who sets the charges

Nearly every line on the bill is a wholesale charge set by your regional water company, and it's identical whichever retailer bills you. Retailers add a margin of roughly 2–7% on top, which is why the difference between retailers is small compared with the difference between regions.

SPIDs

Each bill carries Supply Point IDs, 13-character references for the water and sewerage supply points at your premises. They identify where the property connects to the network, not the meter itself. On shared or converted buildings, one site can have several.

Leak allowances

If a hidden leak causes a spike in usage, the retailer can apply to the wholesaler for a leak allowance, which reduces the billed volume. It's normally limited to one claim per customer, and it's calculated from normal usage once the leak has been repaired.

More on business water