Best fixed energy tariff under the price cap (UK)
Find out when a fixed tariff can genuinely beat the Ofgem price cap — and how to check the unit rates, standing charges and fees that matter for your home.
- Understand what “under the price cap” really means (and what it doesn’t)
- Compare fixed vs variable with realistic UK examples and clear assumptions
- Get a whole-of-market quote in minutes — no obligation to switch
Important: the Ofgem cap applies to variable tariffs. “Under the cap” for a fix means your estimated annual cost is below the current cap level for your region and payment method — results vary by usage, meter and tariff terms.
Fast answer: what is the “best” fixed tariff under the price cap?
There isn’t one single “best” fixed tariff for everyone in the UK — because whether a fix is under the Ofgem price cap level depends on your region, payment method (direct debit, prepayment, cash/cheque), meter type (single-rate, Economy 7, smart), and your annual usage.
In practice, the best fixed tariff under the cap is usually the one that meets all of these for your home:
1) Lower total estimated annual cost
Your quoted annual cost on the fix (unit rates + standing charges) comes out below the cap level for your region/payment type.
2) Exit fees you can live with
Some fixes have exit fees per fuel. If prices fall or you move, those fees can wipe out the benefit.
3) Terms match how you pay
Payment method discounts and prepayment pricing vary. Always compare like-for-like.
Key takeaway: The price cap is not a maximum bill and it doesn’t cap fixed tariffs. It’s a limit on what suppliers can charge on standard variable (and certain default) tariffs, expressed through maximum unit rates and standing charges. “Under the cap” is an estimated comparison against cap levels for your situation.
Good reasons to choose a fix (even if it’s only slightly under)
- You value predictable unit rates for budgeting.
- You’re on a standard variable tariff and want to reduce exposure to future cap rises.
- The fix is meaningfully cheaper for your usage pattern, with manageable exit fees.
When a fix may not be best
- You may move soon (tenancy ending, house sale progressing).
- The fix has high exit fees and only a small advantage.
- You have very low usage — standing charge differences can dominate.
Compare fixed tariffs under the cap for your home
To see if a fixed tariff is under the current cap level for your situation, you need a personalised quote — not a headline “typical bill” figure.
What we’ll use to compare (in plain English)
- Where you live (your postcode determines the distribution region).
- How you pay (direct debit, prepay, or on receipt of bill).
- Your meter setup (single rate, Economy 7, smart meter).
- Your usage (kWh per year) — if you don’t know it, we can estimate.
No pressure: getting a quote doesn’t lock you into switching. You’ll be able to review tariff details (including unit rates, standing charges, exit fees and contract length) before deciding.
Get your quote
Enter your details and we’ll show available fixed tariffs and how they compare for your postcode and usage. Fields marked optional help us tailor results.
How to check whether a fixed tariff is genuinely “under the price cap”
Suppliers may market a fix as “below the cap” using a typical home and a specific region/payment method. To check properly:
Step 1: Compare the right things
- Unit rate (p/kWh) for electricity and gas
- Standing charge (p/day) for each fuel
- Payment method (Direct Debit vs prepay can differ)
- Meter type (single rate vs Economy 7)
Step 2: Run an annual cost estimate
Use your yearly kWh (from bills or your online account). Then calculate:
- Annual cost (per fuel)
- (Unit rate × annual kWh) + (Standing charge × 365)
- Add it up
- Electricity annual cost + Gas annual cost = total estimate
Caveat: The Ofgem cap is set via maximum unit rates and standing charges by region and payment method. You can’t confirm “under the cap” accurately from a national average alone. Use a postcode-based comparison and always check tariff PDFs or product details.
Scenario A: Medium-use dual fuel (Direct Debit)
Assumptions (illustrative):
- Electricity: 2,900 kWh/year
- Gas: 12,000 kWh/year
- Fixed tariff rates (example): Elec 24.5p/kWh + 50p/day; Gas 6.1p/kWh + 30p/day
| Fuel | Estimated annual cost |
|---|---|
| Electricity | (0.245×2,900) + (0.50×365) ≈ £893 |
| Gas | (0.061×12,000) + (0.30×365) ≈ £841 |
| Total | ≈ £1,734/year (before any fees/discounts) |
What this tells you: you can now compare this total against the cap-based typical annual cost for your region/payment method, or compare directly to your current tariff using the same usage inputs.
Scenario B: Low-use flat (electricity only)
Assumptions (illustrative):
- Electricity: 1,600 kWh/year
- Fixed tariff rates (example): 25.0p/kWh + 55p/day
| Item | Estimated annual cost |
|---|---|
| Units | 0.25×1,600 = £400 |
| Standing charge | 0.55×365 ≈ £201 |
| Total | ≈ £601/year |
Why low usage can change the answer: standing charges can make up a large share of the bill. A tariff with a slightly higher unit rate but lower standing charge can be cheaper for low-use homes.
Fixed vs variable: what to compare (beyond the headline)
Use this table to sanity-check whether a fixed tariff that’s advertised as “below the cap” is likely to be right for you. Then confirm with a postcode-based quote and the tariff’s key facts/terms.
| What you’re checking | Fixed tariff | Standard variable (price-capped) | Why it matters |
|---|---|---|---|
| Unit rates & standing charges | Set for contract term (usually). Can still change in limited circumstances (e.g. VAT change). | Can change when the cap updates (typically quarterly). | A fix protects you from cap rises, but may leave you paying more if cap falls. |
| Exit fees | Often yes (per fuel), especially for longer fixes. | Usually no. | High exit fees reduce flexibility if a cheaper deal appears. |
| Contract length | Commonly 12–24 months (varies by supplier). | No fixed term. | Longer fixes can offer stability, but more “lock-in”. |
| Discounts & payment method | Direct Debit versions can price differently from prepay/cash. | Cap level differs by payment method and region. | Always compare on the same payment method, or you’ll get the wrong answer. |
| Meter type | May have different rates for single-rate vs Economy 7. | Cap includes separate levels for certain meter setups. | Economy 7 can look cheap/expensive depending on day/night split. |
Decision checklist (quick)
- I’m comparing the same region and payment method.
- I’ve checked both unit rates and standing charges (gas + electricity).
- I’ve looked for exit fees (per fuel) and the contract end date.
- I know my approximate annual usage (or I’m using a reasonable estimate).
- I’ve confirmed whether it’s single rate, Economy 7, or smart/time-of-use.
If you’re time-poor: the 2 numbers to prioritise
- Estimated annual cost using your kWh (not “typical” alone).
- Total exit fees you’d pay if you left early.
Those two usually tell you whether “under the cap” is meaningful for you.
Costs, exclusions and common pitfalls (UK-specific)
“Under the cap” isn’t the same as “cheapest”
A fix can be under the cap but still not the best deal for you if its standing charge is higher and you use less energy than the “typical” benchmark.
Exit fees can change the outcome
If the cap falls or you find a better tariff later, exit fees (often charged per fuel) can erase savings. Check the total fee before choosing.
Economy 7 and time-of-use need extra care
For Economy 7, your day/night split matters. A tariff with a lower night rate but much higher day rate may cost more overall if you don’t shift enough use overnight.
Prepayment pricing differs
The cap level and available tariffs can be different for prepayment meters. Always compare prepay-to-prepay unless you’re actively changing meter/payment method.
Other things that can affect your results
- Regional standing charges: can vary significantly across Great Britain (distribution networks differ).
- Moving home: you may be able to take a tariff with you, but it depends on supplier and property eligibility.
- Billing and Direct Debit: your monthly payment amount is a budget estimate; your bill is based on actual usage and meter reads.
- Northern Ireland: energy markets and price structures differ from Great Britain; always check NI-specific comparisons.
FAQs
Does the Ofgem price cap apply to fixed tariffs?
No. The cap limits charges on standard variable and certain default tariffs. Fixed tariffs can be priced above or below cap levels; you need to compare the rates and total estimated cost for your home.
Why do “under the cap” deals look different by postcode?
Because standing charges (and cap levels) vary by region, driven mainly by distribution network costs. Payment method and meter type also change the cap level and available pricing.
What if I don’t know my annual kWh usage?
Check a recent bill, your online account, or your in-home display (smart meter) history. If you can’t access it, you can use a reasonable estimate — but the “under the cap” conclusion will be less reliable.
Can I switch if I’m in debt to my supplier?
Often yes, but it depends on the type/level of debt and whether you have a prepayment meter. In some cases, debt may need to be repaid or arranged before switching. Citizens Advice has guidance for different situations.
Will a fixed tariff change my Direct Debit amount?
Possibly. Suppliers often set Direct Debits to spread estimated annual costs over the year. Your payment amount can change with new rates or after meter reads; your actual bill is based on energy used.
If I rent, can I choose a fixed tariff?
Usually yes if you pay the energy bills and your tenancy agreement doesn’t include energy as part of rent. If bills are included, your landlord/agent may control the contract.
What happens at the end of a fixed deal?
You’ll typically move onto the supplier’s standard variable tariff unless you choose another deal. Set a reminder before the end date so you can compare again and avoid rolling onto higher rates.
Could a fix be “under the cap” but still cost me more?
Yes. If your usage is lower than assumed, standing charges dominate. Or if you have Economy 7 and don’t use enough electricity off-peak, the tariff can be a poor fit even with a low headline figure.
Trust, methodology and sources
Editorial ownership
- Written by
- EnergyPlus Editorial Team
- Reviewed by
- Energy Specialist
- Last updated
- May 2026
How we assess “best fixed tariff under the cap”
We treat “best” as the fixed tariff that provides the lowest estimated annual cost for a household, while also remaining practically suitable (reasonable exit fees, contract length and payment/meter compatibility).
- Inputs used: postcode (region), payment method, meter type, and annual consumption in kWh (electricity and/or gas).
- Cost basis: (unit rate × kWh) + (standing charge × 365). All figures are estimates.
- Under the cap check: we compare against cap levels relevant to the user’s region and payment method, recognising the cap is implemented via maximum unit rates and standing charges for standard variable tariffs.
- Suitability filters: we highlight exit fees, contract length, and any key eligibility constraints shown in tariff details.
Limitations: Your actual bills depend on real usage, tariff terms, meter readings/estimates, and any changes allowed within contract conditions. Promotions and availability can change quickly, and not every household is eligible for every tariff.
Ready to check fixed deals under the cap for your postcode?
See available fixed tariffs, compare total estimated costs, and review exit fees before you decide.
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