Business water and wastewater, on a single retail contract
Purely Energy is a whole-of-market business utilities broker. We tender the retail layer of the Open Water market across UK wholesale regions, show you the wholesale price, retail margin and our margin separately, and stay with your account for the term. B-Corp certified, ISO 9001 accredited, no hidden fees.
What is on a UK business water bill?
Last updated: May 2026. Refreshed alongside the Ofwat PR24 cycle.
Wholesale (not negotiable)
Set by your regional wholesaler under Ofwat's PR24 price review. Covers the volumetric water charge (pence per cubic metre), the standing/fixed charge per meter, and the wastewater charge (foul, surface-water and highway drainage). Roughly 80 to 95 per cent of a typical bill.
Retail (where we compete)
The retailer's margin, billing, query handling, anomaly alerting and account management. Open to competition since April 2017 in England, 2008 in Scotland. We tender this layer across the retailer panel we work with and consolidate multi-site portfolios onto a single contract.
Indicative business water charges by size
Wholesale-led ranges across the major regional wholesalers, as at May 2026. Retail margin and any consolidation saving sit on top of these figures.
| Business size | Typical annual usage | Water (£/m³) | Wastewater (£/m³) |
|---|---|---|---|
| Micro business (e.g. small shop, cafe, salon) | Under 1,000 m³/yr (< 1 million litres) | £1.20 to £1.90 per m³ | £1.30 to £2.20 per m³ |
| Small business (office, restaurant, small workshop) | 1,000 to 10,000 m³/yr | £1.10 to £1.85 per m³ | £1.25 to £2.10 per m³ |
| Mid-market (multi-site retail, hotels, schools) | 10,000 to 50,000 m³/yr | £1.00 to £1.75 per m³ | £1.15 to £2.00 per m³ |
| Large / I&C (manufacturing, large estates) | Over 50,000 m³/yr | £0.85 to £1.55 per m³ | Trade-effluent (Mogden formula): varies by load |
Figures exclude retailer margin and any per-meter standing charges. Trade-effluent sites are billed under the Mogden formula rather than the standard wastewater rate.
UK water wholesalers by region
Wholesale water in England and Wales is supplied by regional monopolies regulated by Ofwat. Scotland has a single national wholesaler. Your site's wholesaler determines the non-negotiable part of your bill; we layer competitive retail on top across every region in your portfolio. The OpenStreetMap below highlights every wholesaler, its approximate region and the seven areas the Environment Agency has classified as seriously water-stressed.
MOSL Power BI snapshot, March 2026
Supply points (SPIDs)
~2.6M
Non-household water and sewerage SPIDs on CMOS across England. Roughly 1.2 million businesses, charities and public-sector customers sit behind them.
Wholesalers
12
Regional wholesalers in the English non-household market. Plus Welsh Water, Hafren Dyfrdwy and Scottish Water across the wider UK (17 on the map).
Active retailers
22
Business Stream (~392k SPIDs) and Castle Water (~199k) lead, with Water Plus, Wave Utilities and Pennon Water Services completing the top five by volume.
Stress exposure
60%
Share of non-household water consumption in regions the Environment Agency classifies as seriously water-stressed. Seven wholesaler areas qualify; they are dashed on the map.
For the live split by service category, retailer and wholesaler, MOSL publishes a quarterly Power BI dashboard: mosl.co.uk supply-points dashboard. Market opened to competition on 1 April 2017 (England); Scotland opened in 2008.
Full wholesaler list (table)
| Wholesaler | Region | Service |
|---|---|---|
| Anglian Water | East Anglia, Lincolnshire, Northamptonshire, Cambridgeshire | Water and sewerage |
| Northumbrian Water | North East England (Northumberland, Tyne & Wear, Durham, parts of Tees Valley) | Water and sewerage |
| Severn Trent Water | Midlands, mid-Wales border, parts of South Yorkshire | Water and sewerage |
| South West Water | Devon, Cornwall, parts of Dorset and Somerset | Water and sewerage |
| Southern Water | Kent, Sussex, Hampshire, Isle of Wight | Water and sewerage |
| Thames Water | Greater London, Thames Valley, parts of Surrey and Berkshire | Water and sewerage |
| United Utilities | North West England (Cumbria, Lancashire, Greater Manchester, Cheshire, Merseyside) | Water and sewerage |
| Wessex Water | Dorset, Somerset, Wiltshire, parts of Hampshire and Gloucestershire | Water and sewerage |
| Yorkshire Water | West, North and East Yorkshire | Water and sewerage |
| Hafren Dyfrdwy | North-east and mid-Wales border (former Dee Valley area) | Water and sewerage |
| Dŵr Cymru / Welsh Water | Most of Wales and parts of western England (Herefordshire) | Water and sewerage |
| Affinity Water | Parts of Hertfordshire, Bedfordshire, Buckinghamshire, Surrey, Essex and east London | Water only |
| Portsmouth Water | South-east Hampshire and the Isle of Wight | Water only |
| South East Water | Kent, East and West Sussex, Surrey, Berkshire, Hampshire | Water only |
| South Staffs Water (incl. Cambridge Water) | South Staffordshire, parts of Worcestershire and Cambridgeshire | Water only |
| SES Water (Sutton & East Surrey) | Parts of Surrey, Kent and south London | Water only |
| Scottish Water (wholesale) | Scotland (single national wholesaler) | Water and sewerage |
How to switch business water retailer
- 01
Audit your sites
Pull your most recent water bills (one per site is enough). We map every SPID, confirm the wholesale region, current retailer, meter type, and any existing trade-effluent or surface-water charges.
- 02
Tender the retail layer
Wholesale is fixed by region; the retail margin is competitive. We tender across our Open Water retailer panel and present every offer with margins shown separately.
- 03
Switch, validate, monitor
The retailer-to-retailer switch is handled through MOSL's CMOS system with no service interruption. Every invoice runs through bill validation and anomaly alerts trigger on unexpected consumption.
Why use Purely Energy as your business water broker
Whole-of-market retailer panel
Open Water market tender across the retailers we work with, not a single referral partner.
Margins shown separately
Wholesale charge, retailer margin, and Purely margin each shown on every quote. No hidden uplifts.
Multi-region consolidation
One contract, one invoice and one renewal date across every wholesale region in your portfolio.
Wastewater + trade effluent
Mogden formula calculations, surface-water rebate audits, and consent paperwork handled in-house.
Leak and anomaly alerts
Overnight flow, weekend usage and step-changes flagged within hours, not the next bill cycle.
Account team for the term
Named account manager, validation every invoice, renewal alerts 6 to 12 months before contract end.
Frequently asked questions
The ten most common questions UK businesses ask about water procurement, pricing and switching, answered by our Warrington procurement team.
- Which UK businesses can choose their water retailer?
- Any non-household customer in England has been able to choose their water retailer since the Open Water market opened on 1 April 2017. Scottish non-household customers have had that right since 2008 under Scotland's earlier reforms. Wales is partially open: Welsh businesses using more than 50 megalitres per year can switch retailer. Household (domestic) customers cannot switch.
- What is the average business water rate?
- There is no single national rate. Wholesale water charges are set by your regional wholesaler (Severn Trent, Thames Water, United Utilities, Anglian, Yorkshire and others) under Ofwat's PR24 price review covering 2025-2030, and they are not negotiable. As at May 2026, our indicative ranges sit roughly between £0.85 and £1.90 per cubic metre for water volumetric, plus £1.15 to £2.20 per cubic metre for wastewater, with significant variation between regions. The retail layer (the bit that competes) is typically 5 to 15 per cent of the total bill; that is where a tender adds value.
- Does switching change my actual water supply?
- No. The physical wholesaler that pumps water to your site and removes wastewater does not change. What changes is the retailer that meters, bills, validates and serves your account. Service quality from the wholesaler is unaffected: outages, mains repairs and emergency response are the wholesaler's responsibility regardless of who bills you.
- How do you tender business water contracts?
- Send us your most recent water bills (one per site is enough). We map every SPID (Supply Point Identifier) and confirm the wholesale region, current retailer, meter type, and any trade-effluent or surface-water charges already on the account. Then we run the retail layer through our Open Water retailer panel and present a side-by-side comparison with the wholesale price, retail margin and our margin shown separately. Decision is yours, contract is yours, and we stay with the account for the term.
- What is wastewater (sewerage) and is it included?
- Wastewater covers foul sewage (everything that goes down a drain inside the building), surface-water drainage (rain falling on the property that enters the public sewer), and highway drainage (run-off from adjacent roads). Most retailer contracts cover all three. Many sites pay surface-water charges on areas that actually drain to soakaway or watercourse instead of the public sewer; we audit every account for rebate eligibility going back six years where applicable.
- What is trade effluent and Mogden formula?
- Industrial sites discharging anything other than ordinary domestic sewage need a trade-effluent consent, regulated under the Water Industry Act 1991. Charges are calculated using the Mogden formula, which weights the volume, suspended solids (Ms) and chemical oxygen demand (Os) of the effluent against treatment costs. We handle the consent paperwork, the sampling regime and the year-on-year Mogden review for any site where trade effluent applies. Mid-market food-and-drink, chemicals, pharmaceutical and laundry sites are typical candidates.
- Do I pay VAT on business water?
- Water and sewerage supplied to non-industrial customers (most offices, retail, education, hospitality) is zero-rated for VAT. Industrial customers in certain SIC code ranges (1 to 5: extraction, manufacturing, construction, energy, mining) pay the standard 20 per cent VAT rate. There is no Climate Change Levy on water. Your retailer is required to apply the correct VAT category from your SIC code; we double-check this during onboarding because mis-classification is one of the most common bill errors we find.
- How long is a typical business water contract?
- Open Water retail contracts typically run for 1 to 3 years. Shorter terms (1 year) let you retender more often as more retailers enter the market; longer terms (3 years) lock in service-level commitments and any retail-margin discount. Our team typically recommends a 2 year term for mid-market portfolios, with renewal alerts 6 to 12 months before the end date. Out-of-contract / deemed rates apply if you let a contract roll past its end date, exactly as they do in gas and electricity.
- Can you handle multi-site portfolios across wholesale regions?
- Yes. Single-retailer consolidation across regions is one of the biggest reasons mid-market and I&C buyers switch. Each site keeps its local wholesale tariff (set by Anglian, Severn Trent, Yorkshire, Thames or whoever the regional wholesaler is), but you get one invoice, one renewal date, one account manager, and one set of leak alerts across every site. We can also handle hybrid English-Scottish portfolios.
- What happens if there is a leak or unexpected high usage?
- Half-hourly and daily meter reads (where the meter supports them) feed anomaly detection that flags overnight flow, weekend usage and step-changes within hours rather than the next bill cycle. For sites without an automated meter we provide a monthly review of consumption against baseline. Suspected leaks are escalated to the wholesaler for investigation and we manage the leak-allowance claim on your behalf where the leak is downstream of the meter.
Water guides
Open Water: how the non-household market works
English non-household sites have had retail choice since 1 April 2017. Ofwat sets PR24 wholesale prices region by region; your retailer competes on billing, leak alerts and trade-effluent support.
Switching your business water retailer
The tender to switch-completion window is roughly 6 to 8 weeks: 30 days RWPS notice plus the wholesaler-led transfer. Your supply never changes, only who bills you and the SLAs that wrap it.
Auto-renewals and deemed-rate tails
Miss the renewal window and you fall onto deemed rates set by your retailer. The Open Water deemed tail typically sits 20 to 40 per cent above tendered pricing, paid until you switch or accept a new contract.
VAT and CCL on water bills
Water and sewerage are zero-rated for VAT for most business customers, with some industrial activity falling to 20 per cent under the Industry Division 1 list. Climate Change Levy does not apply to water.
Reading a UK business water bill
Wholesale (volumetric + standing), retail margin, sewerage, surface-water drainage and trade effluent line up separately on the bill. Knowing which lines compete tells you where a tender adds value.
Smart water metering and leak alerts
Half-hourly water logging spots overnight flow within days of fitting. On most commercial sites the saved leak volume pays for the logger and monitoring service within a single quarter.
Multi-site water consolidation
One retailer can invoice across all UK regions for a single non-household portfolio. Useful for cost allocation by site, payment-run discipline, and a single phone number for outages and trade effluent.
Water reporting for SECR and CDP
SECR doesn't require water disclosure but CDP Water Security does for many large multi-site businesses. Your consolidated invoicing makes the disclosure data straightforward to assemble.
Case studies
Good Taste Bakery
Multi-utility procurement across food-production sites. Demonstrates the consolidated-billing pattern we apply to water portfolios across UK regions.
Watford Grammar School
Education-sector portfolio with consolidated billing across a multi-site estate. The same operating model used to tender water for trust-wide academies.
PTS Property
100+ properties across a residential and commercial portfolio. Cost allocation and SLA discipline carry directly into Open Water tendering.
Bosvena School
kVA review plus monitoring saved £26,347 a year. The same demand and bill-line analysis exposes water overconsumption on independent and trust-run school sites.
Ready to consolidate every water account?
Send us your most recent bills, one per site is enough. We come back with an Open Water market tender, a consolidation plan, and any surface-water rebate opportunities we spot.