A water invoice covers more than the water that comes in. Most of the cost sits in charges that are assumed rather than metered.
Verification
- Verified as at:
- Last reviewed by:
- Omnium
Figures in this sheet were current at the verification date above. Regulated charges reset each April. If you are relying on a figure, check the source or ask us.
A4 board pack. Cover page, then a running head and foot on every page.
How a business water bill is built
A business water invoice covers more than the water that comes in. In England, retail services are open to competition, so the retailer named on your invoice bills you, while the wholesale charges within it are set by the regional wholesaler. Most invoices carry four kinds of line.
| Line | What it is for |
|---|---|
| Water supplied | Volume through the meter, plus a fixed or standing charge related to meter size. |
| Waste water | Foul sewerage, usually charged on an assumed proportion of the water supplied. |
| Surface water and highway drainage | Rainwater drainage from the site, often charged on site area or rateable value rather than on anything metered. |
| Trade effluent | Where the site discharges something other than domestic waste water, under consent. |
What to check, in order
The meter reads. Are they actual or assessed? An assessed or estimated charge continuing for long periods is the single most common reason a water bill does not reflect the site.
The meter itself. Does the serial number on the invoice match the meter on site, and is the meter size the one you are being charged a standing charge for?
Every SPID on the account. Supplies at sites you have left, or belonging to a neighbouring occupier, are billed on for as long as nobody checks.
The waste water proportion. Where a large share of the water supplied does not return to the sewer, for example water lost to evaporation, taken into a product or used for irrigation, the assumed return figure may not fit the site.
The drainage basis. Surface water charges rest on an assumption about how the site drains. Where rainwater does not enter the public sewer, that assumption is worth testing against a site plan.
Continuous night flow. A metered site that never reads zero overnight is usually paying for a leak, and paying for the waste water on it as well.
A leak is two charges, not one
Water lost through a leak is charged as water supplied and, in most cases, charged again through the waste water line applied to that volume. That is why an unresolved leak on a metered supply moves cost faster than most billing errors, and why overnight consumption is the first thing to read on a water account.
Changing retailer is not the fix
Retail competition affects the retail element of the charge, which is the smaller part of most invoices. Getting the meter reads, the SPID list, the return-to-sewer assumption and the drainage basis right acts on the larger part. Do that first, then look at who bills you.
Related sheets
- Invoice validation
What goes wrong on energy invoices, how validation works against the contract, and why we validate for payment rather than approve.
- Controlling utility cost across several sites
How to hold an estate as one record, compare sites fairly, and find the losses that only appear when a business runs more than one site.
- Reading your energy bill
What every line on a commercial gas and electricity bill means, so you can check it is right and see which parts you can influence.
Take this sheet into a meeting
Checking a business water invoice exports as an A4 board pack: a cover page carrying the title and the verification date, then the sheet itself with a running head and foot on every page.
If this sheet raises a question about your own sites, speak to us.