How business energy contracts end: deemed vs rollover explained
Most businesses find out how their energy contract ends the hard way: a bill arrives that looks nothing like the last one. Unlike domestic energy, business supply has no price cap and very few automatic protections, so what happens at the end of your contract is decided almost entirely by two things — what your contract says, and whether you acted before the deadline written inside it.
The three ways a business energy contract can end
When a fixed-term business contract reaches its end date, one of three things happens:
- You have already agreed a new contract — either a renewal with your current supplier or a switch to a new one — and it starts the day the old one ends. This is the outcome you want, and it is the only one you fully control.
- You are rolled over. Many contracts contain a clause letting the supplier extend you onto a new fixed term — often 12 months — if you did not serve notice in time. Rollover terms are set by the supplier, not negotiated, and they are rarely the supplier's most competitive offer.
- You fall onto out-of-contract or deemed rates. If no new agreement is in place and no rollover applies, the supplier keeps supplying you on its default terms. These are typically the most expensive terms a supplier publishes, because they price in the risk of supplying a customer with no commitment.
Deemed rates: paying for having no contract
Deemed contracts arise when energy is being supplied without any agreed contract at all — most commonly when a business moves into new premises and starts using energy before agreeing terms with the incumbent supplier. You still have to pay (the law treats consumption as acceptance), but the supplier sets the rates unilaterally. Deemed rates also catch businesses whose fixed term expired with nothing agreed, depending on the supplier's terms.
The practical advice is simple: if you have just moved into premises, contact the supplier (or a broker) immediately. Every week on deemed terms is money you did not need to spend, and there is nothing stopping you agreeing a proper contract straight away.
Rollover contracts: the quiet renewal
A rollover happens when your contract renews automatically because you missed the notice window. The trap is in the mechanics:
- The notice window is defined by the supplier, and it can pass months before your contract actually ends.
- Suppliers must send renewal notices, but they arrive amid ordinary post and are easy to miss in a busy business.
- Once rolled, you are typically locked in for the new term, with termination fees if you leave early.
For micro-businesses — broadly, businesses with few employees or relatively low annual energy consumption, as defined in supplier licence conditions — regulators have progressively tightened the rules on rollovers and notice periods, and suppliers must show key contract terms more clearly. But the protections are narrower than most owners assume, and medium-sized businesses fall outside most of them entirely.
Finding your dates before they find you
Three dates matter, and they are all in your contract or on your renewal letter:
- Contract end date — when your fixed term expires.
- Notice window — when you are allowed to tell the supplier you are leaving. Serve notice in writing and keep the acknowledgement.
- Renewal offer date — when your supplier will write with its renewal terms. Treat this as the starting gun, not the deal.
If you cannot find your contract, ask the supplier directly — they must tell you your end date and notice requirements. A broker will do this legwork for you and log the dates so the window is never missed again.
What good looks like
Well-run businesses treat energy like any other supplier relationship: diarise the notice window the day you sign, get quotes across a broad panel of suppliers when the renewal window opens, and have the new contract signed before the old one ends so supply rolls seamlessly from one agreement to the next. Remember that switching never interrupts supply — same wires, same pipes, same meter — so there is no operational risk in changing supplier, only the administrative risk of doing nothing.
One more thing worth knowing: businesses generally do not get a cooling-off period on energy contracts the way domestic customers do. Once you sign, you are committed — which is exactly why the comparison should happen before the signature, not after.
Where a broker fits in
A good broker tracks your end dates, serves notice on time, compares the market against your actual consumption profile, and handles the switch paperwork. SwitcherMate Ltd is paid a commission by the supplier if you switch — never a fee from you — and discloses that arrangement openly. If you want the renewal handled properly this year, the quote form on our homepage takes under a minute and a UK-based specialist will call you back.
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