Who is the cheapest of the Big Six energy suppliers? (2026)

Last Updated: 14th August 2026

Key Takeaways: At a Glance

• Regulatory Update: The Ofgem Price Cap rose 13% on 1 July 2026 and is set at £1,663/year for a typical household until 30 September. Ofgem confirms the October cap by 26 August, and forecasters expect a further rise of roughly 2–4%.
• Cheapest Big Six Fixed: British Gas (Fix and Boiler Bonus v9) is currently the market leader at ~£128/month (£1,533/year).
• Best Long Fix: E.ON Next (Next Fixed 24m v58) is a close second at ~£129/month, and locks the price in for two years.
• Market Trend: Switching to the cheapest Big Six fix saves roughly £77 per year against the region’s standard variable rate — and the cheapest fix on the whole market saves about £162.

Energy bills remain a significant expense for UK households. After a 13% jump in the Price Cap on 1 July, many consumers are asking: Which of the Big Six energy suppliers offers the cheapest rates right now?

The truth is, there is no single “cheapest” supplier for everyone. Prices vary based on location and usage. However, the latest data for August 2026 shows that British Gas has taken the lead with the lowest fixed price, with E.ON Next just behind it on a two-year deal.

Who are the Big Six energy suppliers?

The “Big Six” refers to the largest energy suppliers in the UK. Historically, this group dominated the market. Today, following mergers and the rise of challengers, the Big Six includes:

• British Gas (Largest supplier, serving millions of homes).
• Octopus Energy (The tech-led giant that recently joined the top tier).
• EDF Energy (Major player with significant low-carbon generation).
• E.ON Next (Digital-focused brand absorbing Npower customers).
• Scottish Power (Key player in renewable wind generation).
• OVO Energy (Expanded significantly after acquiring SSE).

While their market share has shifted due to competition, these companies still supply the vast majority of UK households.

Which of the “Big 6” suppliers is the cheapest? (August 2026)

Understanding the difference between fixed and variable tariffs is critical to saving money in the current market.

• Variable Tariffs: Fluctuate with the Ofgem Price Cap. Most Big Six variable tariffs are priced identically at the cap level. In the East Midlands, Standard Variable Tariffs are sitting at £1,611/year (~£134/month); Ofgem’s headline national figure is £1,663/year.

• Fixed Tariffs: Lock in a price for 12–24 months. Currently, these are generally cheaper than the government Price Cap.

The Verdict: Who is the Cheapest?

• Cheapest Big Six Fixed: British Gas is the winner for pure price. Their Fix and Boiler Bonus v9 tariff costs approximately £1,533/year (£128/month) over a 15-month term. This is roughly £77 cheaper per year than staying on the variable Price Cap in the same region.

• Best Long Fix: E.ON Next is a very close second. Their Next Fixed 24m v58 tariff is ~£1,546/year (£129/month) and holds that price for two years.

• Best if you don’t want to lock in: Octopus Energy’s price-capped Flexible tariff works out at ~£1,548/year (£129/month) once the £50 switching credit is counted, and carries no exit fee at all. If you would rather have a tracker proper, British Gas Cap Tracker Plus Sep27 v1 is ~£1,551/year with a £50 exit fee, and E.ON Next and EDF Energy are within £10 a year of that.

• Most Expensive: Among the Big Six, Scottish Power and OVO Energy currently have the priciest fixed deals, at £146 and £142/month respectively — both above the standard variable rate. Anyone with those suppliers is generally better off on the price-capped tariff for now.

💡 Smart Tip: You could get £50 credit right now! Octopus Energy is frequently rated the cheapest and best for service. Get a free quote in less than 30 seconds plus £50 credit when you switch: https://localenergyprices.co.uk/credit

If you’d like to compare all suppliers, find the cheapest energy supplier right now in our up-to-date guide.

Alternatively, you can find the cheapest supplier in your area by searching here.

Customer satisfaction and service

Price is only half the story. Service quality ensures your bills are accurate and issues are resolved quickly.

Which of the Big Six has the best customer reviews? (Trustpilot)

• Octopus Energy is consistently ranked highly for customer service and satisfaction. They are rated 4.8 on Trustpilot from over 837,000 reviews.
• British Gas has a rating of 4.4 on Trustpilot from over 350,000 reviews.
• EDF has a rating of 4.8 from over 243,000 reviews on Trustpilot.
• E.ON Next is rated 4.5 from over 219,000 reviews on Trustpilot.
• Scottish Power has over 198,000 reviews and is rated 4.4 in total.
• OVO Energy has a rating of 4.7 from over 293,000 Trustpilot reviews.

Which of the Big Six has the best customer service? (Citizens Advice)

For an independent view on complaints handling and call waiting times, Citizens Advice ranks suppliers quarterly. As of August 2026:

• Top Tier: E.ON Next (3.71/5, 3rd overall) and Octopus Energy (3.67/5, 4th overall) — the only two Big Six suppliers in the top half of the table.
• Mid Tier: OVO Energy (3.30/5) and Scottish Power (2.94/5).
• Lower Tier: EDF Energy (2.90/5) and British Gas (2.61/5, 13th of 15) score lowest, with British Gas recording 68.7 complaints per 10,000 customers — the highest of the six.

Customer service can be measured through various indicators, including:

• Response times to queries
• Accuracy of bills
• Ease of contacting customer support
• Resolution of issues

We have highlighted the results of each of the Big Six energy suppliers below:

Is it worth fixing energy prices in 2026?

With the energy market still fluctuating, the decision to fix depends on the Price Cap forecast.

The 2026 Outlook

The Ofgem Energy Price Cap is reviewed every three months (Quarterly).

• Current Status (August 2026): The cap is £1,663/year, after a 13% rise on 1 July.
• Forecast: Ofgem announces the October cap by 26 August 2026. Cornwall Insight currently forecasts £1,700 — about 2% higher — and that figure already allows for the government scrapping the 5% VAT on electricity from 1 October.
• Recommendation: Fixing remains a smart move. The cheapest fixed deals are already 5–10% below the current cap, and every published forecast has the cap rising rather than falling this autumn. Fixing now secures immediate savings and protects you from further increases over the winter.

Which are the greenest Big Six Energy suppliers?

Many Big Six suppliers now offer green tariffs to meet the growing demand for eco-friendly power. These options can vary in cost and sustainability commitments.

Green tariffs and offers

Most Big Six suppliers provide renewable electricity tariffs. These plans typically use 100% renewable sources like wind, solar and hydro. Some also offset gas usage.

Octopus stands out among the Big Six, offering one of the cheapest renewable tariffs on the market. Their green plans often cost about the same as standard ones. E.ON Next also offers a dedicated green fix, Next Gust 12m v59, at around £138/month.

You may find green add-ons too. These let you pay extra to support renewable projects. Check if suppliers buy directly from generators or just purchase certificates.

Supplier commitments to sustainability

Beyond tariffs, Big Six suppliers have broader sustainability goals. Many aim to generate more renewable power themselves. They’re investing in wind farms, solar parks and other green tech.

Look at their plans to cut emissions. The best performers generate renewable power and buy it straight from generators. Some offer smart home gadgets to help you save energy.

Check for flexible time-of-use tariffs. These reward you for using power when renewable supply is high. A few suppliers even pay decent rates if you export solar energy to the grid.

Emerging competition to the Big Six energy providers

New companies are shaking up the UK energy market. They’re bringing fresh ideas and lower prices to challenge the Big Six suppliers. In August 2026 every one of the five cheapest tariffs on the market comes from outside the Big Six.

Utility Warehouse takes a different approach. They bundle energy with other services like broadband and mobile phones.

Ecotricity stands out for its 100% green energy. They even make their own power from wind and sun, and their two-year EcoFixed deal is currently one of the cheapest on the market at around £125/month.

So Energy lets you vote on where they buy renewable energy from. This gives you a say in your power supply.

Frequently Asked Questions

1. Will energy prices go down later in 2026?

Not on current forecasts. The Price Cap rose 13% on 1 July to £1,663, and Cornwall Insight expects a further rise of about 2% in October, to roughly £1,700. Ofgem confirms the October figure by 26 August. One piece of good news: the government is scrapping the 5% VAT on electricity from 1 October until the end of March 2027, worth around £45 a year to a typical household — but that is already built into the forecast above.

2. Should I fix my energy tariff or stay on the variable rate?

The general advice for August 2026 is to fix. The cheapest fixed tariffs (British Gas at £128/m among the Big Six, or around £121/m across the whole market) are meaningfully cheaper than the variable cap, and with the cap forecast to rise again in October and January, a fix looks likely to stay ahead for the next year.

3. Is the “RTS Switch-off” real, and does it affect me?

It was real, and it is now finished. The Radio Teleswitch Service (RTS) was phased out in stages from June 2025 and the final signal was switched off on 30 June 2026. If you had an old Economy 7 or storage-heater meter driven by a radio signal and it has not been replaced, your heating and hot water may no longer be switching correctly — contact your supplier straight away to book a smart meter installation. There is nothing left to wait for.

4. Do I legally have to accept a smart meter?

Technically, no, smart meters are not a legal requirement for standard supply. However, many of the cheapest tariffs (including most modern fixed and tracker deals) now mandate a smart meter as part of the contract’s Terms & Conditions. Additionally, if you had an RTS meter (see above), you effectively must upgrade to keep your heating working properly.

5. Who is eligible for the Warm Home Discount (£150) this winter?

The Winter 2026/27 scheme is worth £150 and reopens in October 2026. It covers England, Scotland and Wales only — there is no Warm Home Discount in Northern Ireland.

• Qualifying date: 23 August 2026. Your circumstances on that date decide whether you get it.
• England and Wales: everyone who qualifies is in the automatic “core group”. You need to be receiving Universal Credit, Housing Benefit, income-related Employment and Support Allowance or Pension Credit, and your name (or your partner’s) must be on the electricity bill.
• Scotland works differently: there is a core group paid automatically and a “broader group” who have to apply directly to their own supplier, which sets its own extra criteria.
• Note: your supplier has to be part of the scheme, and the discount is credited to your electricity bill rather than paid to you in cash.

6. Why are standing charges still so high?

Standing charges (the fixed daily cost) cover the maintenance of the national grid and the cost of failed suppliers. Under the July 2026 cap they average around 57p/day for electricity and 29p/day for gas, partly because some policy costs (like green levies) have been moved onto them. Ofgem is reviewing this, and a low standing charge option is now available on the cap, but the headline rates have barely moved.

7. What happens if my energy supplier goes bust?

You are protected by the Ofgem Safety Net.

• Don’t Panic: Your gas and electricity supply will not be cut off.
• Sit Tight: Ofgem will appoint a “Supplier of Last Resort” (SoLR) to take over your account.
• Credit Balances: Any credit you had with the old supplier is protected and will be transferred to the new one.
• Action: Take a meter reading immediately, but do not try to switch until the new supplier contacts you.

8. Does switching energy suppliers affect my credit score?

It depends on the supplier.

• Soft Check: Most suppliers (and comparison sites) only do a “soft search” to check your identity. This does not affect your credit score.
• Hard Check: Some suppliers may perform a “hard search” if you choose a specific tariff or payment method (like paying on receipt of bill rather than Direct Debit).
• Tip: If you are applying for a mortgage soon, stick to suppliers that only use soft checks or ask them beforehand.

9. Can I switch energy suppliers if I am renting?

Yes. If your name is on the energy bill, you have the legal right to switch suppliers to get a cheaper deal. You do not need your landlord’s permission, though it is polite to inform them. If your landlord pays the bill (it’s included in your rent), you cannot switch, but you can ask them to do so.

10. Is an Economy 7 tariff still worth it in 2026?

Economy 7 gives you cheaper electricity for 7 hours at night but charges a higher rate during the day.

• Worth it if: You have electric storage heaters or an Electric Vehicle (EV) that you charge overnight. You typically need to use more than 40% of your power at night to break even.
• Not worth it if: You have gas central heating. Modern “smart tariffs” (like Octopus Agile or Tracker) often provide cheaper off-peak rates than traditional Economy 7 without the expensive day rates.