Energy bills and tariffs use a lot of jargon, and the words that matter most are often the least clear: standing charge, exit fee, deemed, deadlock. This glossary explains each term in plain English, with today's figures and what to check. Terms are grouped by where you'll meet them.
This is general information, not legal or financial advice. Figures are as of 14 October 2026, for the price cap period 1 October to 31 December 2026.
What do the terms on your energy bill mean?
| Term | What it means | What to check |
|---|---|---|
| kWh | A kilowatt hour, the unit energy is sold in. A 1 kW heater running for one hour uses 1 kWh. | Your yearly kWh for each fuel. It's on your bill or app, and it's the key number for comparing tariffs. |
| Unit rate | The price per kWh, in pence. Under the October to December 2026 cap, the average Direct Debit rate is 26.32p for electricity and 7.97p for gas. | Your own rates are on your bill. They vary by region and payment method. |
| Standing charge | A fixed daily charge you pay even if you use no energy. The cap averages are 54.83p a day for electricity and 29.68p a day for gas. | See standing charges explained. |
| Meter reading: actual (A) or estimated (E) | "A" means a real reading. "E" means your supplier guessed. | Several estimates in a row can mean a big catch-up bill. Send readings. |
| MPAN and MPRN | Your electricity supply number (MPAN) and gas supply number (MPRN). | Useful when switching or reporting a problem. |
| Single-rate meter | One price for electricity at all times. | Most homes have one. |
| Economy 7 / time-of-use | Electricity that's cheaper at set hours (often at night) and dearer at other times. | It only saves money if you use a lot in the cheap hours. Check the exact times on your bill. |
| Smart meter | A meter that sends readings automatically. | It ends estimated bills, but it doesn't lower prices on its own. |
| Credit balance | Money you've paid in advance that you haven't used yet. | You can ask for it back. See is your Direct Debit too high? |
| Debit balance / arrears | Money you owe for energy already used. | If you're struggling, ask your supplier for a payment plan. |
| VAT | Household electricity in Great Britain has 0% VAT from 1 October 2026 to 31 March 2027. Gas stays at 5%. Northern Ireland electricity stays at 5%. | See no VAT on electricity until March 2027. |
For what each charge means line by line, see your energy bill explained.
What do the price cap terms mean?
| Term | What it means |
|---|---|
| Energy price cap | The most a supplier can charge per kWh and per day on a standard variable tariff. It caps the rates, not your total bill: use more, pay more. It changes on 1 January, 1 April, 1 July and 1 October. See the price cap explained. |
| Typical bill | Ofgem's example yearly bill under the cap: £1,723 from 1 October 2026, for a home on Direct Debit using 2,500 kWh of electricity and 9,500 kWh of gas. |
| Typical domestic consumption values (TDCVs) | Ofgem's low, medium and high usage figures, revised from 1 July 2026: electricity 1,600 / 2,500 / 3,800 kWh and gas 6,000 / 9,500 / 14,000 kWh a year. |
| Standard variable tariff (SVT) | The default tariff, covered by the cap. Prices change each quarter. You can leave at any time without an exit fee. |
| Fixed tariff | Unit rates and standing charges fixed for a set time, often 12 months. Not covered by the cap. See fixed or variable? |
What do the switching and contract terms mean?
| Term | What it means | What to check |
|---|---|---|
| Exit fee | A charge for leaving a fixed tariff early. With 49 days or less left on a fixed deal, you can switch without one. | The fee per fuel, and your end date. |
| Cooling-off period | 14 days to cancel a new contract without a fee, starting the day after you agree it. | Cancel in writing and keep a copy. |
| Switching time | A switch should take no more than 5 working days, unless you ask to wait. Your new supplier tells your old one. | You don't need to cancel your old account yourself. |
| Final bill | When you switch or move, your old supplier must send your final bill within 6 weeks, or pay you £40. Any credit should be refunded within 10 working days after that. | See switching energy supplier. |
| Deemed contract | What you're on when you move into a home and use energy without choosing a tariff. | Contact the supplier, give a meter reading and choose a tariff. |
| Direct Debit | A fixed monthly payment set by your supplier to spread costs across the year. | It should match your expected use. You can challenge it. |
| Prepayment | Paying for energy before you use it, by top-up or smart prepay. Prepayment standing charges are now the same as Direct Debit ones. | Ask about emergency credit and help if you can't top up. |
What do the rights and complaints terms mean?
| Term | What it means |
|---|---|
| Back-billing | A bill for energy used in the past. Suppliers can't bill you for energy used more than 12 months before the bill, unless you stopped them billing accurately. See back-billing. |
| Deadlock letter | Your supplier's written final answer to a complaint. It lets you go straight to the Energy Ombudsman. |
| 8-week rule | If your complaint isn't resolved after 8 weeks, you can take it to the Energy Ombudsman. |
| Energy Ombudsman | The free service that settles disputes with energy companies. Its decision is binding on the supplier if you accept it. |
| Priority Services Register (PSR) | Free extra help from your supplier and network if you're of state pension age, pregnant or have young children, disabled, have a long-term health condition, need powered medical equipment, or are going through a difficult time. It includes a password scheme for callers and notice of planned power cuts. You need to join again if you switch. |
| Warm Home Discount | £150 off your electricity bill for eligible households in winter 2026/27. See Warm Home Discount. |
| Winter Fuel Payment | £100 to £300 for people of State Pension age, depending on age and circumstances. See Winter Fuel Payment. |
| Cold Weather Payment | £25 for each 7-day spell at 0°C or below, from 1 November 2026 to 31 March 2027, for people on certain benefits. See Cold Weather Payment. |
How do the terms fit together? A worked example
A home uses the medium amounts: 2,500 kWh of electricity and 9,500 kWh of gas a year, on Direct Debit, at the October 2026 cap averages.
- Electricity: 2,500 × 26.32p = £658.00, plus 365 × 54.83p = £200.13. Total £858.13.
- Gas: 9,500 × 7.97p = £757.15, plus 365 × 29.68p = £108.33. Total £865.48.
- Together: about £1,724 a year, or about £144 a month. That matches Ofgem's typical bill of £1,723 (the small gap is rounding).
If this home's Direct Debit were £180 a month, it would be paying about £435 a year more than it's likely to use. That would be worth a Direct Debit check.
Check your own figures with our free estimator. It's an estimate, not a quote, and EnergyQuote.ai isn't a supplier, broker or comparison site.
What to do next
- Find your yearly kWh for electricity and gas on your bill or app.
- Note your unit rates, standing charges, tariff name and end date.
- If you're on a fixed deal, diary the date 49 days before it ends.
- Send a meter reading if your last bill was estimated.
- Check your Direct Debit against your expected yearly cost.
- Join the Priority Services Register if it applies to anyone in your home.
- Keep complaints in writing. After 8 weeks, or a deadlock letter, go to the Energy Ombudsman.
Sources
- Ofgem: Energy price cap unit rates and standing charges
- Ofgem: Review of typical domestic consumption values, decision (PDF)
- Citizens Advice: Switch energy supplier or tariff
- Citizens Advice: Claim back credit from your energy supplier
- Ofgem: What to do if you get a back bill
- Ofgem: Join your supplier's Priority Services Register
- GOV.UK: VAT on fuel and power (VAT Notice 701/19)
- Energy Ombudsman