Cheapest green gas and electricity tariff in the UK
Find genuinely good-value green energy deals for your home — based on your postcode, meter type and how you pay. We’ll explain what “green” really means, how to compare like-for-like, and how to avoid common pitfalls.
- Whole-of-market comparison: green electricity and (where available) green gas options
- UK-specific guidance for smart meters, prepay, Economy 7 and regional pricing
- Transparent methodology and realistic cost examples (estimates, not guarantees)
Prices and availability vary by region, meter type and payment method. “Cheapest” is based on estimated annual cost for your details, including standing charges.
Fast answer: the “cheapest green tariff” depends on your exact details
In the UK, there isn’t one universal cheapest green gas and electricity tariff. Prices vary by postcode (regional network costs), meter type (single-rate, Economy 7, smart), payment method (Direct Debit vs prepayment), and how much energy you use.
Key takeaways (what matters most)
- Compare total annual cost (unit rates + standing charges), not just the headline unit price.
- “Green electricity” often uses REGOs — still legitimate, but quality varies. Look for clear sourcing and additionality.
- “Green gas” is usually carbon offsetting or a small % biomethane blend. 100% biomethane is less common and can cost more.
- Check exit fees, variable vs fixed, and whether the tariff fits your meter (especially Economy 7).
If you want the cheapest green option
- Use your postcode and recent usage (kWh) if you have it.
- Filter to renewable electricity tariffs and choose your preference for green gas.
- Compare estimated annual cost and contract terms side-by-side.
- Switch online — you typically won’t need an engineer visit.
Important caveat about “cheapest”
A tariff that’s cheapest today may not stay cheapest. If you prefer price stability, a fixed green tariff can be a better fit even if the first-year estimate is slightly higher. Always check what happens after the fixed term ends.
Compare green tariffs with your details
Tell us a few basics and we’ll show green electricity tariffs and green gas options available for your home. We use your details to calculate estimated annual cost (unit rates + standing charges), so you can compare like-for-like.
What you’ll need (30–60 seconds)
- Your postcode
- How you pay (Direct Debit / on receipt / prepay)
- Your meter type (if known)
- Optional: last bill usage in kWh for best accuracy
What counts as “green” here?
We highlight tariffs marketed as renewable/green by the supplier. We also explain the difference between renewable-backed electricity (often using REGOs) and green gas (offsetting or biomethane).
Tenant? You can usually switch if you pay the energy bills and have an individual meter. If your bills are included in rent, you typically can’t choose the supplier.
Get your quote
We’ll use these details to provide your comparison and help you switch. Estimates vary by supplier terms, meter set-up and regional charges.
How to choose the cheapest green gas and electricity tariff (UK)
To find the cheapest green deal you can actually switch to, you need to compare tariffs on total cost, then sense-check the green claims and terms. Here’s a practical, UK-specific approach.
1) Start with your usage (kWh), not your spend
If you can, use annual kWh from your bill (electricity and gas). If you only know monthly spend, comparisons are less precise because prices may have changed since your last bill.
2) Compare the annual estimate (inc. standing charges)
Two tariffs can have similar unit rates but very different standing charges. Always compare the estimated annual cost for your region and payment method.
3) Check you’re eligible (meter + payment)
Some tariffs exclude prepayment or Economy 7, or price them differently. If you have multi-rate, make sure the day/night split assumptions match how you use electricity.
4) Sense-check the “green” label
Look for clear statements about renewable electricity backing (often REGOs) and what “green gas” means (offsets vs biomethane). If this matters to you, prioritise transparency and certification over marketing language.
Two realistic scenarios (with numbers)
These examples show how “cheapest” changes by usage, standing charges and the type of green add-on. Figures are illustrative estimates to help you compare; your quotes will differ by region and tariff.
Scenario A: 1–2 bed flat (low usage), single-rate
- Assumptions
- Electricity 2,000 kWh/year; gas 6,000 kWh/year; paying by monthly Direct Debit; single-rate meter.
- Illustrative comparison
- Tariff 1 has slightly higher unit rates but lower standing charges — and can work out cheaper at low usage. Adding a “green gas” option (often offsets) might add ~£20–£80/year depending on supplier.
Scenario B: 3–4 bed house (higher usage), looking for price certainty
- Assumptions
- Electricity 3,600 kWh/year; gas 14,000 kWh/year; monthly Direct Debit; single-rate meter; preference for a 12-month fix.
- Illustrative comparison
- A fixed green tariff can be slightly higher than the cheapest variable green tariff at the start, but may feel better if you want predictable payments. If a fixed deal includes an exit fee, factor that in if you might move home or switch again soon.
What “green gas” usually means (and why it affects price)
Most homes on the gas grid receive natural gas. “Green gas” tariffs typically do one of the following:
- Carbon offsetting linked to your gas usage (common; cost varies; quality differs by project).
- Biomethane matching/blending (a % of your usage matched with biomethane injected into the grid).
- 100% biomethane claims (less common; may be higher-priced; check exactly how the supplier defines it).
Tip: If your main goal is cutting carbon impact at home, switching to renewable electricity is often the simplest first step. Longer-term, options like insulation and low-carbon heating can matter more than a “green gas” add-on.
Comparison table: what to check before you call it “cheapest”
Use this table to compare tariffs you see in your results. It focuses on the factors that most often change the true cost and suitability for UK households.
| Check | Why it matters | What to look for | Common mistake |
|---|---|---|---|
| Estimated annual cost | Shows the combined effect of unit rates + standing charges for your usage. | Quote based on your postcode, meter type and payment method. | Comparing unit rates only. |
| Standing charges | Can dominate costs for low usage households. | Electricity and gas standing charge (p/day) for your region. | Assuming standing charges are the same everywhere. |
| Fixed vs variable | Fixed gives predictability; variable can change with the market. | Fix length, what happens at end of term, and any price protections. | Choosing a fix without checking end-of-fix rates. |
| Exit fees | Can wipe out savings if you switch early or move. | Fee per fuel, and any fee-free window near end of term. | Not checking fees on dual-fuel deals. |
| Meter compatibility | Economy 7 and prepay tariffs can price differently or be excluded. | Tariff explicitly supports your meter type and payment method. | Switching without confirming Economy 7 rates and times. |
| Green credentials | “Green” can mean different things across suppliers. | Clear explanation of renewable electricity backing and any gas offset/biomethane approach. | Assuming all green tariffs have the same impact. |
Quick checklist: who cheapest green deals tend to suit
- You can pay by monthly Direct Debit (often best-priced).
- You can provide kWh usage (more accurate comparisons).
- You’re happy with renewable electricity backed by certificates, and you’ll review “green gas” carefully.
- You’re comfortable switching online and submitting meter readings (if needed).
And who it may not suit (or needs extra checks)
- Prepayment customers (fewer deals; pricing differs).
- Economy 7 homes with high day-time usage (cheap night rate may not help).
- Households likely to move soon (exit fees matter).
- Anyone wanting verified additionality (you’ll need to read supplier disclosures carefully).
If you’re unsure, compare first — then decide
It’s normal to see a mix of fixed and variable green tariffs. Start by ranking by estimated annual cost, then filter by contract length, exit fees and the type of green claim you’re comfortable with.
Costs, exclusions and common pitfalls (UK green tariffs)
The cheapest green tariff on a comparison table can become the wrong choice if you miss the details below. These are the issues our team sees most often.
Standing charges can outweigh unit rates
Low usage homes often do better with lower standing charges, even if the unit rate is a little higher. Always compare the full annual estimate.
Economy 7 assumptions might not match your life
Multi-rate tariffs work best if you use a meaningful share of electricity overnight (e.g., storage heating, EV charging). If you mostly use power in the day, costs can rise.
Prepayment availability is more limited
Some green tariffs are not available for prepay meters, or are priced differently. If you’re in prepay, prioritise eligibility first.
Exit fees and end-of-fix rates
A fixed tariff can have exit fees. Also check what tariff you move onto when the fix ends — that rate may be higher unless you switch again.
Direct Debit discounts (and payment risk)
Direct Debit is often cheapest. If you miss payments, suppliers can change your payment method or request a different payment plan.
“Green” wording can be unclear
Some tariffs emphasise green electricity but say little about gas. If “green gas” is important, look for explicit detail on biomethane vs offsets.
Avoid this common trap
Don’t assume a dual-fuel deal is always cheaper. Sometimes electricity and gas are better value from different suppliers — but managing two accounts isn’t for everyone. Compare both ways if you’re cost-focused.
FAQs: cheapest green gas and electricity tariffs (UK)
Are green tariffs always more expensive?
Not always. Some renewable electricity tariffs can be competitively priced. “Green gas” add-ons are more likely to add cost, depending on whether it’s offsets or biomethane matching.
What does “100% renewable electricity” mean in the UK?
It usually means the supplier matches the electricity they sell with renewable certificates (commonly REGOs). That can be valid, but the best suppliers explain their approach clearly and publish fuel mix information.
Can I get truly “green gas” to my home?
If you’re on the gas grid, the physical gas in the pipes is mixed. “Green gas” tariffs generally use offsets or match a portion of your usage with biomethane injected elsewhere into the grid. Definitions vary by supplier.
Do green tariffs work with smart meters?
Yes. A smart meter doesn’t restrict you from choosing a green tariff. If you’re switching supplier, your smart meter should usually continue working, but in some cases smart functionality can be affected temporarily.
Will I lose supply if I switch?
Normally, no. Switching is an administrative process. You should continue to receive gas and electricity throughout. You may be asked for a meter reading around the switch date for accurate final billing.
Is it cheaper to switch both fuels together?
Sometimes, but not always. Dual-fuel can be convenient, but you should compare the total annual cost against separate suppliers too — especially if you’re prioritising the cheapest green electricity.
I’m on prepay — can I still get a green tariff?
Possibly, but the number of tariffs can be smaller. Some suppliers offer renewable electricity options for prepay, but availability and pricing vary by region and meter arrangements.
What details change the price the most?
Your region (postcode), payment method (Direct Debit vs prepay), meter type (single-rate vs Economy 7), and your actual kWh usage. Standing charges can be especially important for low usage homes.
Trust, methodology and sources
Trust signals
- Written by
- EnergyPlus Editorial Team
- Reviewed by
- Energy Specialist
- Last updated
- May 2026
How we assess “cheapest green” (our approach)
We aim to help you find the lowest estimated annual cost for tariffs marketed as renewable/green that are available to your household. Where possible, we encourage users to compare on a like-for-like basis.
- Cost basis: estimated annual cost using your usage inputs (kWh where available), including unit rates and standing charges.
- Availability filters: postcode/region, payment method, and meter type (including multi-rate where supported).
- Green flags: tariffs labelled by suppliers as renewable/green; we advise checking supplier disclosures for detail on REGOs, biomethane matching, and offsets.
- Suitability checks: fixed/variable, contract length, exit fees, and any exclusions.
Limitations (please read)
- Quotes are estimates. Your actual bills depend on future prices (for variable tariffs), your real consumption, and any changes to standing charges.
- Some suppliers present “green” differently; we recommend verifying the supplier’s own tariff and fuel mix documents before switching.
- Economy 7 and multi-rate households may see different results if the day/night usage split differs from assumptions.
Helpful UK sources
Editorial standards (what we won’t do)
We don’t promise guaranteed savings, and we avoid blanket claims like “this is the cheapest tariff in the UK” without your specific details. Where we provide examples, they are illustrative and clearly labelled as estimates.
Ready to see your cheapest green options?
Compare whole-of-market home energy tariffs using your postcode and meter details. It’s the quickest way to find a green deal that fits your home and budget.
Reminder: If you’re in a fixed contract, check exit fees and whether you’re within any fee-free switching window before you proceed.
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