Who Is My Business Water Supplier?
Use this free interactive tool to find who supplies water to your UK business. Enter your postcode to see your regional water wholesaler, then learn how to identify and switch the retailer that bills you.
Free interactive water supplier lookup
Enter a UK business postcode to find your likely water wholesaler.
For UK business premises only. We never cold-call domestic customers.
Confirm my exact water supplier
We will identify your current retailer, contract end date and rate, then call you back. For UK business premises only.
How this helps your business
To find who supplies your business water, enter your postcode in the tool above: it returns your regional water and sewerage wholesaler (the monopoly that owns the pipes, fixed by location), and then helps you identify your retailer (the company that bills you, which you can switch). For a UK business there are two answers to “who is my water supplier”, and getting both right is the difference between overpaying on deemed rates and running a competitive tender.
The wholesaler is set by your postcode and cannot be changed. There are around a dozen regional water and sewerage companies in England, such as Thames Water, Severn Trent, United Utilities, Anglian, Yorkshire, Southern, South West, Wessex and Northumbrian, plus several water-only companies (Affinity, South East Water, Portsmouth Water and others) that supply the clean water in some areas while a larger company handles sewerage. Scotland has a single wholesaler, Scottish Water. Wales is served by Dŵr Cymru / Welsh Water and Hafren Dyfrdwy. Our tool maps your postcode area to the likely wholesaler so you know which non-negotiable network charges apply to your site.
The retailer is the part you can switch
The English non-household water market opened to competition on 1 April 2017 (Scotland led the way in 2008). Since then every business in England can choose its water retailer: the company that issues your bill, reads your meter, manages your account and handles queries. Your supply is identified in MOSL’s central market database, CMOS, by a unique SPID (Supply Point Identification number), the water equivalent of an electricity MPAN or a gas MPRN. Switching retailer does not change a drop of your water or risk your supply: the same wholesaler keeps treating and delivering it. What changes is the service, the billing, and the price. Our guide to business water procurement and switching walks through the full process.
Why businesses use this lookup
Most businesses inherit a water account from a previous occupier, a site acquisition, or a default registration, and end up on deemed or out-of-contract rates that are rarely competitive. Multi-site operators are often billed by several retailers across different regions, which makes cost control and reporting painful. Knowing your wholesaler and retailer is the first step to consolidating billing, recovering surface-water drainage and trade-effluent overcharges, and re-tendering at the right time. If you also want to cut consumption, our free business water leak check tool flags whether a hidden leak is inflating your volumetric charges, and you can browse our other free business energy and water tools for electricity and gas supplier lookups too.
How Purely Energy confirms your exact supplier
A postcode narrows down the wholesaler, but only the central market data confirms your exact retailer, SPID, contract end date and current rate. Purely Energy retrieves all of that for you with a free Letter of Authority, so you do not need to dig out an old bill or call round suppliers. We are a B-Corp certified UK business water and energy consultancy managing more than 2,000 sites and over 100 million pounds of annual spend for 500-plus business clients, with 30-plus suppliers on our panel. We work for you, not the suppliers, with no hidden commissions, and our clients typically save 15 to 30 percent. When you are ready, request a free business water quote and we will confirm your supplier and tender the market on your behalf.
Frequently asked questions
- Who is my water supplier for my business?
- Your business water supplier has two parts. The wholesaler owns the pipes and treats your water and sewerage, and is a regional monopoly fixed by your postcode (for example Thames Water, Severn Trent, United Utilities or Scottish Water). The retailer is the company that bills you and runs your account, and since 1 April 2017 every business in England can choose and switch its retailer. Enter your postcode in the tool above to see your likely wholesaler, then we confirm your current retailer.
- Is the water wholesaler the same as my supplier?
- No. The wholesaler (the regional water and sewerage company) maintains the network and cannot be changed. Your supplier in the everyday sense is your retailer, the company that issues your bill, reads your meter and you can switch. Many businesses confuse the two because before April 2017 the regional wholesaler also billed you directly. Today the layers are separate.
- How do I find my water supplier without a bill?
- Use the postcode tool above to identify your regional wholesaler, then have Purely Energy confirm your current retailer through the MOSL central market database (CMOS), which records the retailer registered against your supply point (SPID). You do not need a paper bill: a free Letter of Authority lets us retrieve your supply details, contract end date and current rate for you.
- Can a business switch its water supplier?
- Yes, in England and Scotland. The English non-household water market opened on 1 April 2017 and Scotland's opened in 2008, so any business in either nation can switch its water retailer for better service, consolidated billing across sites and competitive charges. In Wales, only sites using more than 50 million litres of water a year can currently switch. You cannot change your wholesaler because it is a regional monopoly.
- What is a SPID and where do I find it?
- A SPID (Supply Point Identification number) is the unique reference for your water and wastewater connection in the non-household market, held in MOSL's central market database, CMOS. It is the water equivalent of an MPAN for electricity or an MPRN for gas. Your SPID appears on your business water bill. If you do not have a bill, Purely can retrieve it for you with a Letter of Authority.
- Why does my water contract end date matter?
- Your contract end date determines when you can switch retailer without penalty and when you should re-tender to avoid rolling onto expensive deemed or out-of-contract rates. Knowing it ahead of time lets us run a competitive tender across our panel of suppliers and time the switch correctly. Tell us your end date, or we will find it for you, and we will plan the renewal.
- Does Purely Energy charge businesses to find their water supplier?
- No. The lookup tool is free, and confirming your wholesaler and retailer through a Letter of Authority is free. Purely Energy is a B-Corp certified consultancy that manages more than 2,000 sites and over 100 million pounds of annual spend. We work for you, not the suppliers, with no hidden commissions, and typical savings range from 15 to 30 percent.
Find out exactly who supplies your business water
Our team confirms your wholesaler, your current retailer, your contract end date and your rate, then tenders the market for you. For UK business premises only.