EnergyPlus · May 2026

Cheapest green electricity tariff for UK homes (June 2026)

Since Ofgem's October 2024 green-tariff reforms, suppliers selling a tariff as '100% renewable' must back the claim with REGO certificates and disclose how the green electricity is sourced. That gives UK homes a clearer view of what they're buying — and a tighter comparison between cheap REGO-only tariffs (cheapest, weakest claim) and PPA-backed tariffs (slight premium, stronger additionality). In May 2026 the cheapest 100% renewable fixes sit at the cap to ~3% below cap, several no-exit-fee green fixes are at or just below cap, and Big Six green variants now exist alongside specialist suppliers like Good Energy and Ecotricity.

Get a personalised quote Read the fast answer

Editorial information, not financial advice. Prices and policy can change — always confirm against the supplier and Ofgem.

Cheapest green electricity tariff — June 2026 at a glance

In May 2026 the cheapest REGO-only green electricity fixes sit at the April–June 2026 cap to ~3% below cap on typical use, almost matching the cheapest non-green fixes. PPA-backed green tariffs (Good Energy, Ecotricity, Octopus Greener) carry a small premium of 1–4% above the cheapest non-green fix in exchange for direct generator funding. Since Ofgem's October 2024 reforms suppliers must disclose how green claims are backed — REGO-only, REGO + matched PPA, or REGO + matched PPA + carbon-offset gas.

Quick checklist (May 2026):

  • Cheapest REGO-only green fixes: cap to ~3% below cap — almost the same price as non-green.
  • PPA-backed green fixes: 1–4% premium for direct generator support.
  • Ofgem October 2024 reforms enforce disclosure on green claims.
  • Green dual-fuel adds carbon-offset gas — usually a few percent above non-green.
  • Switching to green takes 5 working days under Faster Switching.
Last updated
May 2026
Reviewed by
Energy Specialist
Audience
UK households & small businesses

Get a tailored quote

Share a few details and we’ll match you to suppliers and tariffs that suit your home, meter and usage. The aim is to make quotes comparable — same term, same assumptions — so you can decide with confidence.

What we’ll do with your details: request and present supplier quotes, and contact you about your comparison. You can ask us to stop at any time.

What changes your quote most

Annual kWh

Drives the unit-rate portion of your bill.

Meter type

Single-rate, Economy 7/10, smart, half-hourly all price differently.

Postcode & region

Standing charges and tariff availability vary by network region.

Term & start date

Fixes of 12/18/24/36 months trade certainty for flexibility.

Compare options now

No obligation. If you don’t know your usage, an adviser can help estimate it.

Start your comparison

By submitting, you confirm this is for a UK home energy comparison. We’ll use your details to provide quotes and contact you about your comparison. You can opt out at any time.

Tip: Your MPAN (and MPRN for gas) helps suppliers price more accurately. Both are on a recent bill.

Cheapest green electricity tariff for UK homes in June 2026

A clear, current overview to help you choose with confidence.

What 'green electricity' actually means in 2026

All UK electricity comes from the same shared grid, so 'green' tariffs are about how the supplier matches your usage. REGO certificates prove a matching kWh of renewable electricity was generated somewhere on the grid; PPAs (power purchase agreements) directly fund a generator. Ofgem's October 2024 reforms tightened disclosure rules so suppliers must tell you which mix they use.

REGO-only vs PPA-backed

REGO-only tariffs are usually the cheapest green option — the certificates are inexpensive on their own, so the supplier can sell green at almost the same price as standard. PPA-backed tariffs (Good Energy, Ecotricity, Octopus Greener) commit money to specific generators, with a small premium for that additionality.

Ofgem's October 2024 green tariff reforms

Suppliers selling tariffs as '100% renewable' must publicly disclose the source mix, the PPA percentage, and how unmatched renewable claims are handled. The reforms haven't banned REGO-only tariffs — but they've made the difference between green tiers visible, so consumers can choose with eyes open.

What about gas?

Most 'green' dual-fuel tariffs use carbon-offset natural gas (offsets paid into verified schemes) rather than biomethane (true renewable gas, limited supply). Biomethane-backed gas is available from a handful of specialist suppliers at a higher premium. Offset gas adds typically 1–3% to a dual-fuel green tariff.

Compare like-for-like

Indicative May 2026 view for a typical UK electricity customer comparing green options. Use the form on this page for a personalised comparison.

What to compare Typical range (May 2026) Notes
Default tariff cap (Apr–Jun 2026) Reference baseline Standard variable, no green backing required.
Cheapest REGO-only green fix Cap to ~3% below cap on typical use 100% renewable claim backed by certificates only. Cheapest green option.
PPA-backed green fix (Good Energy, Ecotricity) 1–4% above cheapest non-green fix Direct generator funding. Strongest 'additionality' claim.
Octopus Greener tariff At cheapest non-green fix to ~2% above Mix of REGO + PPA disclosed in supplier reporting.
Standard variable green tariff At cap Same framework as default, with a green badge. No price saving vs default.

How to pick the cheapest green UK electricity tariff (June 2026)

  1. 1. Decide your green standard

    REGO-only (cheapest, weakest impact), PPA-backed (small premium, direct generator funding), or biomethane (strongest, highest premium).

  2. 2. Find your annual kWh

    Use last year's bill or your supplier app — the most recent 12 months of electricity (and gas if dual-fuel).

  3. 3. Check the supplier's post-Oct-2024 disclosure

    Suppliers must publish their source mix and PPA percentage. Check this before signing — it's how you tell REGO-only from PPA-backed.

  4. 4. Compare on annual cost

    Annual cost = (unit rate × kWh) + (standing charge × 365). Add any premium for green vs non-green.

  5. 5. Run a whole-of-market comparison

    Use the form on this page — it surfaces every green tariff for your postcode.

  6. 6. Apply and submit opening reads

    Switching takes 5 working days. Submit electricity and gas opening reads on day one.

Common pitfalls to avoid

The most frequent issues we see when households and businesses act on what looks like a good deal.

  • Assuming all 'green' tariffs are equally renewable — REGO-only and PPA-backed have very different real impact.
  • Paying a green premium without checking the supplier discloses PPA percentage post Oct 2024 reforms.
  • Switching to a green variable at-cap and thinking it's cheaper than the default — it's the same price.
  • Picking a PPA-backed dual-fuel without checking how the gas side is handled (offset vs biomethane).
  • Forgetting that green tariffs follow the same Ofgem cap framework — no special pricing rules.

Cut your bills for good with solar

Compare free, no-obligation quotes from vetted local solar & battery installers.

Frequently asked questions

What's the cheapest green electricity tariff for UK homes in June 2026?

In May 2026 the cheapest REGO-only green fixes from challenger and Big Six suppliers sit roughly at the April–June 2026 cap to ~3% below cap on typical use — almost the same price as the cheapest non-green fixes. PPA-backed green tariffs cost 1–4% more in exchange for direct generator funding.

Are green electricity tariffs more expensive?

Not significantly. REGO-only green tariffs sit almost at the same price as standard tariffs because the certificates are inexpensive. PPA-backed green tariffs (Good Energy, Ecotricity, Octopus Greener) carry a small premium of 1–4% for direct generator funding.

What's a REGO certificate?

Renewable Energy Guarantees of Origin — Ofgem-issued certificates that prove a matching kWh of renewable electricity was generated somewhere on the UK grid. Suppliers buy and retire REGOs to back '100% renewable' claims. The certificates are cheap, which is why REGO-only tariffs are the cheapest green option.

What's a PPA-backed green tariff?

A power purchase agreement is a direct contract between the supplier and a renewable generator (wind farm, solar park, hydro plant). The supplier funds generation directly, which adds 'additionality' — your money is supporting new renewable capacity. PPA-backed tariffs cost 1–4% more than REGO-only.

What changed with Ofgem's October 2024 green tariff reforms?

Suppliers selling tariffs as '100% renewable' must now publicly disclose source mix, PPA percentage and how unmatched claims are handled. Greenwashing claims without backing data are no longer compliant. The reforms didn't ban REGO-only tariffs but made the difference between green tiers visible.

Is green gas available in June 2026?

Limited supply. Most 'green' dual-fuel tariffs use carbon-offset natural gas (offsets paid into verified schemes). True biomethane gas is sold by a handful of specialists like Green Energy UK and Ecotricity at a higher premium — biomethane production is much smaller than the UK gas demand.

Can I switch to a green tariff if I'm renting?

Yes — as the named bill-payer you have the right to switch supplier, including to a green tariff, unless your tenancy agreement specifies otherwise.

Will switching to a green tariff actually reduce my carbon footprint?

On grid carbon, indirectly — UK grid carbon is shared, so your individual usage isn't physically 'green'. The impact of your switch is the funding signal to renewable generation. REGO-only sends a weak signal (certificates are oversupplied); PPA-backed sends a stronger one.

Trust, methodology and sources

Page governance

Reviewed by
Energy Specialist
Last updated
May 2026

How we keep this page current

We refresh this page each month against the latest Ofgem cap, supplier tariff changes and current scheme guidance. Worked numbers are illustrative; quotes you receive via the comparison form are personalised to your meter and postcode.

Editorial independence: our priority is clarity and like-for-like comparison. Where commercial relationships exist, options are still presented on suitability and the information available at the time.

Reputable UK sources we reference

If you spot anything that looks out of date (a rule change, a new scheme), please contact EnergyPlus so we can review and update this page.

Ready to compare?

Get whole-of-market options matched to your meter and postcode. We’ll help you compare like-for-like and explain the terms before you decide.

Start my comparison Read the FAQs

You’re in control: compare options, ask questions, and only proceed if the terms suit you.

Back to Energy Cost Saving Advice



Updated on 12 Jun 2026