Our methodology: how EnergyPlus compares home energy
A transparent, UK-focused explanation of how we collect tariffs, estimate costs and present results—so you can compare with confidence and choose what fits your home.
- Whole-of-market approach: we aim to show a broad range of available home energy options (availability varies by supplier and customer type).
- Clear assumptions: how we estimate annual costs, standing charges and unit rates for different payment methods and meter types.
- People-first results: we highlight what can change your price (region, usage, meter, eligibility and exit fees).
Prices shown on comparisons are estimates based on the details you provide and supplier data at the time of search. Terms, eligibility and availability can change.
Fast answer: what our “methodology” means
Our methodology explains how EnergyPlus gathers tariff information, how we estimate your annual cost, and how we rank and label results. In short: we use your inputs (like postcode and usage) plus supplier tariff data to produce estimated costs, then present options with clear caveats so you can make an informed choice.
What we use
- Your postcode (distribution region affects network charges)
- Your usage (kWh) or household estimate
- Meter type and payment method (e.g., credit, prepayment)
- Supplier tariff details (unit rates, standing charges, terms)
What you’ll see
- Estimated annual and monthly costs
- Key tariff features (fixed/variable, exit fees, discounts)
- Eligibility notes (e.g., smart meter, online-only, DD only)
- Clear “what could change” caveats
What we don’t do
- No guaranteed savings claims
- No “one perfect tariff” promises—fit depends on your home
- No hidden re-ordering to favour a supplier
- No business energy comparisons on this page
Key takeaway: Energy prices and availability are time-sensitive. The most accurate results come from entering your real usage (kWh) from recent bills and selecting the correct meter and payment method.
Compare energy the way we calculate it
To estimate your costs, we need a few details that affect pricing in Great Britain, including your postcode region and how you pay. If you’re unsure about usage, you can still compare—just note that results are more approximate.
What makes the biggest difference
- Postcode / region
- Network charges vary by distribution area, so the same tariff can cost different amounts in different regions.
- Payment method
- Some tariffs are Direct Debit-only; prepayment options can be different.
- Meter type
- Single-rate vs Economy 7 (and smart meter requirements) can change which tariffs are suitable.
How we estimate annual cost
In most cases we use:
- Standing charge (p/day) × 365
- Unit rate (p/kWh) × your usage (kWh)
- For multi-rate tariffs (e.g., Economy 7): day + night rates with your split where provided
Important: We show estimated costs for comparison. Your actual bills depend on actual consumption, meter reads/smart reads, and any changes to tariff terms.
What we show (and what we may not)
Included in comparisons
- Tariff unit rates and standing charges provided by suppliers/partners
- Estimated annual and monthly costs based on your inputs
- Key terms (fixed/variable, contract length, exit fees where available)
- Eligibility constraints we’re told about (e.g., DD-only, online-only)
May be limited or unavailable
- Tariffs not open to new customers at the time of search
- Supplier-exclusive tariffs not shared with third parties
- Highly bespoke offers (e.g., bundled services) that can’t be fairly standardised
- Some regional/meter-specific tariffs where data is incomplete
Transparency: “Whole-of-market” means we aim to compare across a broad range of suppliers and tariffs available to UK households. Availability depends on suppliers sharing tariffs, your eligibility and what’s open to new customers.
How we rank results (and what each label means)
By default, results are typically ordered by estimated annual cost for the tariff and payment method you’ve selected. We also surface key “fit” information so you can avoid false economies (for example, a cheap tariff that requires Direct Debit when you need prepayment).
| What you see | What it means | What can change it |
|---|---|---|
| Estimated annual cost | Standing charge(s) + unit rate(s) applied to your usage assumptions. | Your kWh, rate changes (variable tariffs), meter reads, VAT (domestic), and any price updates from suppliers. |
| Fixed / variable | Fixed: unit rate typically locked for a term; Variable: can change with supplier pricing. | Supplier price changes, end-of-fix dates, and product withdrawals. |
| Exit fee | A charge for leaving a fixed tariff early (where applicable and disclosed). | Timing of switch, supplier rules, and cooling-off/penalty windows. |
| Payment method | How you pay (e.g., Direct Debit, cash/cheque, prepayment) which can affect rates and eligibility. | Supplier acceptance, credit checks (where relevant), and whether you can change payment method. |
Decision checklist: who this suits
- You have a recent bill (or smart app) showing kWh usage.
- You know your meter type (single-rate vs Economy 7) and how you pay.
- You want a clear view of estimated costs plus key terms like exit fees.
- You’re happy to compare on total annual estimate, not just unit rate.
Who it may not suit (without extra checks)
- You’re on complex metering (e.g., multiple registers) and don’t know your splits.
- You need a tariff tied to a specific bundle or loyalty scheme not widely listed.
- You’re moving home and don’t yet know the meter type/MPAN/MPRN details.
- You can’t meet eligibility requirements (for example, Direct Debit-only).
Two realistic scenarios (with numbers)
These examples show how estimates are calculated. They are illustrative and not a promise of what you will pay. We use simple maths so you can sense-check any quote.
Scenario A: Gas + electricity, single-rate, Direct Debit
- Electricity usage: 2,900 kWh/year
- Gas usage: 12,000 kWh/year
- Electricity unit rate: 24.5p/kWh; standing charge: 52p/day
- Gas unit rate: 6.2p/kWh; standing charge: 30p/day
Estimated annual electricity cost: (2,900 × £0.245) + (365 × £0.52) = £710.50 + £189.80 = £900.30
Estimated annual gas cost: (12,000 × £0.062) + (365 × £0.30) = £744.00 + £109.50 = £853.50
Total estimated annual: £1,753.80 (about £146/month)
Assumptions: 365-day year; rates illustrative; VAT/rounding may apply; bills depend on actual reads and supplier billing cycles.
Scenario B: Electricity-only, Economy 7 (day/night split)
- Total electricity usage: 3,600 kWh/year
- Night share (assumed): 40% (1,440 kWh night; 2,160 kWh day)
- Day rate: 29.0p/kWh; night rate: 14.0p/kWh
- Standing charge: 50p/day
Estimated annual energy: (2,160 × £0.29) + (1,440 × £0.14) = £626.40 + £201.60 = £828.00
Estimated annual standing charge: 365 × £0.50 = £182.50
Total estimated annual: £1,010.50 (about £84/month)
Assumptions: your actual day/night usage split can materially change the result; check your meter registers or supplier app where possible.
How to use these examples: If a quote looks much cheaper, check standing charges, your usage assumptions, and whether the tariff requires a different payment method or meter type.
Costs, exclusions and common pitfalls (UK-specific)
Energy comparisons can go wrong for perfectly understandable reasons—especially around meter types and eligibility. Here are the most common issues and how we handle them.
Exit fees and end dates
Fixed tariffs may include exit fees if you leave before the end date. We show exit fees where available, but always check the supplier’s tariff information before you proceed.
Payment method restrictions
Some tariffs require monthly Direct Debit; others are designed for prepayment meters. If you select the wrong method, the cheapest-looking tariff may not actually be available to you.
Meter type mismatch
Economy 7 tariffs assume day and night usage. If your home doesn’t actually use much at night, a single-rate tariff could be better even if the night rate looks attractive.
Regional pricing differences
Standing charges and unit rates vary by electricity distribution region and (for gas) local transport costs. That’s why postcode is essential for meaningful estimates.
Discounts and bundles
Some deals depend on add-ons (e.g., boiler cover) or conditional discounts. We aim to flag notable conditions, but the supplier’s full terms are the final source.
Moving home
If you’re moving, you may need to start by taking meter readings and checking the meter type at the new property. Comparisons are easier once you know what’s installed.
Practical tip: If you can, take your annual kWh from the last 12 months of bills (or your in-home display/app). “£ per month” on a bill can include debt repayments or budget plans, so kWh is usually a cleaner input for comparisons.
FAQs
Is EnergyPlus “whole of market”?
We aim to compare across a broad range of UK household energy tariffs and suppliers. In practice, what you can see depends on supplier participation, your eligibility, and what’s available to new customers at the time you search.
Why do you need my postcode?
Energy prices vary by region due to network costs. Your postcode helps identify the correct electricity distribution area so we can show more accurate standing charges and unit rates.
Do your results include the Ofgem price cap?
The Ofgem price cap applies to default tariffs for many households, not all tariffs. Our comparison uses the rates and charges supplied for each tariff and your usage assumptions; it doesn’t assume that all tariffs track the cap.
Can I compare if I’m on a prepayment meter?
Yes, but tariff availability can differ for prepayment. If you’re not sure which meter you have, check your top-up method (key/card/app) and your bill details. Selecting the right payment/meter type is essential for meaningful results.
What if I don’t know my kWh usage?
You can still compare using estimates, but treat results as broader guidance. For better accuracy, use your last 12 months’ kWh (gas and electricity) from bills or your online account. If you have Economy 7, try to find your day/night split.
Do you show every tariff from every supplier?
Not always. Some tariffs are exclusive to a supplier’s own channels or may not be shared for third-party comparison. Some products also have complex conditions that don’t standardise well. Where possible, we signpost limitations and encourage checking supplier terms.
Are the prices guaranteed?
No. Prices are estimates based on the details you enter and tariff data available at the time. Variable tariff prices can change. Even fixed tariffs can differ by region and eligibility, and suppliers can withdraw products.
Does switching affect my supply?
Switching supplier shouldn’t interrupt your gas or electricity supply because the same networks deliver energy to your home. The main change is who bills you and the tariff terms you’re on. Timelines and process can vary by supplier and circumstances.
Still unsure? Use the quote form above and tell us what you know. We’ll highlight where assumptions may affect the estimate.
Trust, editorial standards and full methodology
Page details
- Written by: EnergyPlus Editorial Team
- Reviewed by: Energy Specialist
- Last updated: February 2026
Our aim
To help UK households compare tariffs using consistent assumptions and clear caveats—so you can make an informed choice based on estimated cost and suitability, not just headline rates.
How we make money (high level)
EnergyPlus may receive a fee when a customer switches through us or when a lead is submitted (this varies by supplier/partner). We do not promise that paid relationships always produce the cheapest tariff.
How we assess and calculate (step-by-step)
- Collect tariff inputs: We ingest tariff details supplied by energy suppliers/partners (for example: payment method options, unit rates, standing charges, contract term, exit fees where disclosed, and eligibility notes).
- Match to your profile: We use your postcode (region) and your selected fuel (electricity, gas, or dual fuel), meter type, and payment method to filter tariffs that are likely to be relevant.
- Estimate annual cost: We calculate estimated annual charges from standing charges and unit rates applied to your provided/assumed annual usage (kWh). For multi-rate electricity (e.g., Economy 7), we apply the day/night split you provide; if you don’t provide one, we may use a reasonable default split and clearly treat it as an assumption.
- Rank and present: Results are generally ordered by estimated annual cost, with key product features and caveats displayed to support decision-making.
- Quality checks: We run editorial checks to ensure our explanations are consistent and our caveats are prominent, particularly where assumptions can materially change outcomes (usage, multi-rate splits, payment method restrictions, and exit fees).
Limitations (please read): Supplier data can change quickly, and not all tariffs are available in all regions or to all customers. Estimated costs do not include every possible bill adjustment (for example, debt repayments, billing corrections, some bundled add-ons, or changes after the search date).
Sources and further reading (UK)
- Ofgem (Great Britain energy regulator) – guidance on tariffs and consumer protections.
- Citizens Advice: Energy – help with bills, switching and complaints.
- GOV.UK: Energy – official information on support and schemes.
Ready to compare with confidence?
Use your postcode and (ideally) your annual kWh to get a clearer estimate. We’ll highlight key terms like exit fees and eligibility before you decide.
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