What happens to your water account if your retailer goes bust

On a Wednesday evening in February 2020, at six o'clock exactly, Ofwat revoked the licence of a small water retailer called Tor Water. Forty-eight hours later its customers had been parcelled out between four other companies. Almost nobody outside the trade noticed, and that is precisely the problem.

The English non-household water market opened to competition on 1 April 2017. Over the eight years since, around 1.2 million business customers have been free to choose their retailer.¹ Most have not. The market has stabilised around five large operators, a long tail of smaller specialists, and a regulatory safety net that has only had to catch one falling retailer so far. That safety net is now being rebuilt, quietly, in a series of consultations that will shape what happens to your water bill if the next retailer to fail is bigger.

For finance directors signing off utility spend, the relevant questions are short. What actually happens to the bill if my retailer goes under. Where does my money sit. And what does the new regime in 2027 change for me.

How the Tor Water collapse actually unfolded

Tor Water Limited served customers across the South West Water, Wessex Water and Bristol Water regions. On 19 February 2020, Ofwat revoked its licence with effect from 18 the same day. South West Water had terminated Tor Water's wholesale supply contract over a series of unpaid wholesale charges; the underlying issue was a retailer that had collected money from customers but failed to pass on the wholesale portion to the regional monopolies that actually deliver the water.²

Two days later, on 21 February, Ofwat formally asked the Market Operator Services Limited (MOSL) to run what is known as the Interim Supplier Allocation Process. MOSL took the contents of Tor Water's customer book and divided the supply points as equally as possible between four volunteering retailers: Smarta Water, SES Business Water, Water2Business and Yu Water.³ Customers received a letter telling them their new retailer's name and an account reference. There was no interruption to physical water or wastewater services, because the wholesalers (Thames, Severn Trent, Anglian and so on) own the pipes; retailer failure does not touch the network.

That is the model on which the entire safety net rests. It worked, in the sense that the lights stayed on and the taps stayed open. But Tor Water was small, and four retailers had each agreed to take a slice. Nothing in the architecture of the Interim Supply Arrangement (ISA) compels anyone to volunteer. If a larger retailer ever fails, and the available volunteers either decline or cannot absorb the customer book without putting their own balance sheet under pressure, the regulator has a problem.

What happens to your credit balance if your water retailer fails?

The most concrete financial exposure for a buyer in a retailer-failure scenario is not the future bill. It is the credit balance held today.

The Consumer Council for Water (CCW) reported in September 2025 that English water retailers were holding £127 million in credit balances on closed accounts and a further £115 million on live accounts.⁴ That money has been paid by customers in good faith, often through direct debit overpayments that mount up across multiple sites. The Customer Protection Code of Practice (CPCoP) requires retailers to tell customers about credit balances on a minimum quarterly basis and to refund on request. There is no ring-fencing equivalent to the energy market's Supplier Protection Fund. If a retailer enters administration, those credit balances sit inside the administrator's estate alongside every other unsecured claim.

In a clean book sale, this is a non-issue. The acquiring retailer typically inherits the credit balances along with everything else, and the customer notices no change. In a disorderly exit, the position is genuinely unhelpful. Customers can lodge a claim with the administrator and wait. Most do not get the full balance back.

The accounting category matters here. A credit balance held with a business water retailer is an unsecured claim against a regulated counterparty. It earns no interest, carries no ring-fence, and in a disorderly exit converts into a queue position in the administrator's estate. The same treasury policy that governs counterparty credit limits for term deposits should apply. Most do not.

The leak that funds the bad retailer

A credit balance is one silent way money flows out of a business water account. The other is the leak that nobody has measured.

A pinhole leak the size of a sewing needle, on a typical UK mains pressure of 3.5 bar, leaks at roughly 238 litres per hour. Over twelve months, that comes to approximately 2,085 cubic metres of water (and very nearly the same volume of wastewater, because most wholesalers default to charging sewerage on every metered cubic metre). At an average combined unit rate of £4.02 per cubic metre across English wholesalers in 2024-25, the pinhole costs roughly £8,380 a year.⁵ A burst joint or a failed valve, running at one litre per second, costs about £55,000 a year at the same rates.

Detecting that leak is a free five-minute test you can run this afternoon. Turn off every water-using fixture in the building. Read the meter to three decimal places. Wait at least 30 minutes (an hour is better, two if you can spare it). Read again. Any movement, including movement of the small low-flow indicator on a mechanical dial, means the meter is registering water you are not consciously using.

We have published a free water leak cost calculator for businesses that runs the meter-test maths for you. Enter two readings and the elapsed time; it returns the flow rate, the probable annual cost at your regional wholesaler's rates, and a tier-specific checklist of what to do next. No sign-up.

If you find a leak, your retailer can apply for a wholesaler leak allowance. The allowance is a credit applied retrospectively to the volume lost. It is approved by the wholesaler and passed through by the retailer, which is why a competent retailer matters; an incompetent one will quietly bill you for the leak and the wastewater charge on top.

What Ofwat is changing this year

The Interim Supplier Allocation Process was always voluntary. That worked in 2020 because the cost of taking on Tor Water's book was modest. Six years on, retailers in front-line conversations with Ofwat have told the regulator that they will not volunteer for a larger ISA event under the current rules, because they cannot reliably recover the costs of doing so. The customer book brings revenue, but it also brings unbilled consumption, system integration work, and the immediate working-capital strain of running meters and issuing welcome packs before the first payment arrives.

On 27 January 2026, Ofwat published a consultation on two new mechanisms intended to fix this.⁶ The first is a Cost Recovery Mechanism (CRM), a statutory route under which a retailer absorbing an ISA customer book can recover its legitimately incurred costs, either from the failed retailer's estate or from a central industry fund where the estate is empty. The second is a Cashflow Support Tool (CST), a short-term liquidity facility that bridges the gap between accepting customers and receiving the first cycle of payments. Consultation closed on 4 March 2026; the final decision is expected this spring. As of the date of publication, Ofwat has not yet published it.

MOSL's public response, filed in February, called the proposals "an important step" while warning that the regime will only work if it gives retailers genuine confidence that they will be reimbursed.⁷ MOSL also urged Ofwat to align the new mechanism with the January 2026 government White Paper, which proposes legislating a hard supplier-of-last-resort obligation. That would put the current voluntary ISA on a statutory footing similar to the energy market's SoLR regime. As of the date of publication, the legislation has not been introduced.

What is the Retail Exit Code and does it protect your business?

Running alongside the ISA work is a much larger review of the document that decides what you pay if you have never actively chosen your retailer. The Retail Exit Code (REC) sets price caps and other protections for what the market calls "deemed contract" customers, which is most of the 1.2 million eligible English businesses. A deemed customer is one that has not signed a new contract since deregulation in April 2017, or that has been transferred under an ISA event and not yet renegotiated. The bulk of small and many mid-sized businesses sit in this category, paying a default tariff that the REC keeps inside a regulated ceiling.

Ofwat's REC26 review closed for consultation on 8 September 2025. The regulator expects to publish specific reform proposals this spring or summer, with new caps in force from April 2027.⁸ The big argument inside the consultation is where to draw the line between protected and unprotected customers. The UK Water Retailer Council (UKWRC) argued in its submission for lifting price-cap protections from a much larger slice of medium-sized customers, on the grounds that those customers are sophisticated enough to negotiate and that the cap currently keeps the market less competitive than it should be.⁹ CCW pushed back, arguing that the cap is one of the few real consumer protections in the market.

What this means in practice for buyers depends on annual consumption. A business using less than half a megalitre per year (0.5 Ml) will almost certainly remain inside the protected band whatever Ofwat decides. A business between roughly 0.5 Ml and 50 Ml per year sits in the contested zone. Above 50 Ml, the regulator has historically taken a lighter-touch view; expect that to continue.

What you would actually feel if your retailer failed today

Four practical exposures matter, and the answers are different for each.

Billing continuity. Physical water keeps flowing because the wholesaler operates the network. The only outage is administrative. Expect a billing gap of two to six weeks between the failed retailer's last cycle and the new retailer's first invoice. Document your meter reads on the day you receive the transfer letter; that becomes the baseline against which the new account is opened.

Credit balances. This is the live risk. If the retailer's exit is orderly (a planned book sale), credit balances transfer with the customers and you notice nothing. If the exit is disorderly, you become an unsecured creditor in the administrator's estate. The mitigation is operational, not legal: ask your retailer in writing every quarter for a credit balance statement across all sites, and request the immediate refund of anything above a quarter's expected billing.

Trade-effluent consents. These are held by the wholesaler, not the retailer. Existing consents survive any retailer failure intact. The administrative risk is that pending consent applications submitted to the failing retailer (which acts as intermediary) get lost in the transfer. If you have anything in flight, copy the wholesaler directly.

Smart-meter data. Smart meters belong to the wholesaler too. Installations continue. The data feed, however, runs through the retailer's systems on its way to your billing platform or sustainability dashboard. Expect a two- to four-week interruption of automated data feeds while the new retailer's systems are connected. If you have not been offered a smart meter, ask your retailer to escalate it to the wholesaler. The cost to you is nil.

How the new performance regime grades the bad retailer

Ofwat's other big move this year is the Market Performance Framework reform, which went live on 1 April 2025.¹⁰ In essence, the old MPS / OPS regime (which graded wholesalers and retailers on a long list of binary pass/fail metrics) has been replaced by BR-MeX, the Business Customer and Retailer Measure of Experience. BR-MeX measures the service quality experienced by business customers and the retailers acting for them, with financial incentives tied directly to scores. The first full year's scores will be published to wholesalers on 29 May 2026, which is in two weeks.

The practical translation for a buyer is that you can ask any prospective retailer for their BR-MeX score and their quartile ranking and expect a defensible answer. Anything inside the bottom quartile, or any refusal to disclose, warrants written explanation in a tender response.

Three questions to raise with your retailer this quarter

The defensive position for a buyer is unglamorous. It is also cheap.

1. Ask in writing for a credit balance statement across every supply point you operate. Compare the total against a quarter's expected billing. Anything above that requires an immediate refund. If the retailer is slow to answer, treat that as a soft credit-quality signal.

2. Ask for the retailer's most recent BR-MeX score and its quartile ranking. Any retailer competent to handle a business water account in 2026 should be able to produce this without consulting head office. Anything below the bottom quartile warrants a tender process.

3. Run the five-minute meter test once a quarter and file the results with your own utility records. Most leaks announce themselves as a gentle upward drift on a quarterly bill; the meter test catches them at the source while the credit balance dispute window is still open.

The English business water market is in the middle of a regulatory overhaul that began with the Tor Water exit in 2020 and will conclude, on current timelines, when Ofwat itself is replaced by a new single regulator at some point after the Water Reform Bill reaches the statute book. The buyers that come out of that overhaul ahead are the ones who treat their water account as a financial relationship rather than a utility.

Need help reviewing your retailer's credit standing or running a BR-MeX-weighted comparison against peers? Our business water team handles portfolios of every size. Request a free credit and BR-MeX review — we'll come back to you inside two working days.

Written by Faith Labong, Staff Writer at Purely Energy. Peer-reviewed for technical accuracy by Mark Hoffman FCA. Sources retrieved 16 May 2026.

Frequently asked questions

What happens to my water bill if my retailer goes out of business?

Your water keeps flowing because the wholesaler operates the network. Ofwat invokes the Interim Supply Arrangement and asks MOSL to transfer your supply points to one or more volunteering retailers within 48 hours. You receive a letter naming your new retailer and the account reference. Physical service is uninterrupted; expect a billing gap of two to six weeks.

Can I lose money if my water retailer goes bust?

Yes, on credit balances. The Customer Protection Code of Practice does not ring-fence balances against insolvency. CCW reported in September 2025 that £127 million sits in closed-account credit balances across the English market. If your retailer enters administration you become an unsecured creditor in the estate. The mitigation is to request quarterly credit balance statements and refund anything above a quarter's expected billing.

Who decides which retailer takes over a failed retailer's customers?

MOSL, the Market Operator. Ofwat triggers the Interim Supplier Allocation Process; MOSL distributes the supply points across retailers that have volunteered to receive them, aiming for as equal a split as possible. You cannot pre-select your replacement retailer, but you can switch the moment the transfer completes if you prefer.

What is the Interim Supply Arrangement, in plain English?

A regulated safety net. When a water retailer can no longer serve its customers (insolvency, licence revocation or voluntary surrender without an orderly buyer), Ofwat directs MOSL to allocate the customer book across other licensed retailers. Customers are placed on interim terms with their new retailer, with billing subject to the Retail Exit Code's price caps.

What is the REC review and when will it change my bill?

The Retail Exit Code (REC) sets price caps and other protections for water customers who have not actively chosen their retailer. Ofwat is reviewing it now; the consultation closed in September 2025 and the new code is expected to take effect in April 2027. The biggest argument is where to draw the line between protected and unprotected customer size bands. If your annual consumption sits between 0.5 Ml and 50 Ml, the outcome matters to you.

How do I tell if my business has a water leak?

Turn off every water-using fixture, read the meter, wait 30 to 60 minutes with no use, read again. Any movement at all is a leak. Our free water leak checker runs the maths for you, estimates the probable annual cost at your regional wholesaler's rates, and tells you exactly what to ask your retailer next.