Who Are the Big Six Energy Suppliers in 2026? UK Market Guide for Homes & Businesses Quick answer
The Big Six energy suppliers in 2026 are British Gas, EDF Energy, E.ON Next, Octopus Energy, OVO Energy, and ScottishPower. These six providers supply the majority of UK gas and electricity following years of mergers, acquisitions and supplier collapses, and while they remain dominant, switching is easier and faster than ever, and smaller providers continue to offer strong alternatives.
If you would like to read more information or learn more about the pricing of business energy, you can do so here .
How do we work?
Transparent, impartial, and data‑driven reviews made by a team of expert humans, never AI generated – here’s exactly how Compare Your Business Costs helps you find the best deals from trusted UK providers: click here
Authored by: Ally Cox (Business Technology & B2B Services Specialist 10+ Years’ Experience)
Reviewed by: James Ward (Telecoms Specialist, 12+ Years Experience)
Last Updated: August 2026
Contents
The Big Six Energy Suppliers
The State of the UK Energy Market
Risks of a Dominated Market
Barriers to Switching Energy Providers
Recent Collapses of UK Energy Suppliers
The State of the UK Energy Market: February 2026 As of 2025, the current “Big Six” energy suppliers in the UK are:
British Gas EDF Energy E.ON Next Octopus Energy OVO Energy ScottishPower
These suppliers now serve the majority of UK customers following market restructuring between 2020 and 2023.
What Happened to the Old Big Six? The original group (British Gas, EDF, E.ON, ScottishPower, SSE and npower) has changed:
npower → Was absorbed by E.ON
SSE → a domestic customer base acquired by OVO
(This reshuffle is why OVO and Octopus now sit in the “Big Six.”)
The Traditional Big Six Energy Suppliers
Provider Overview Features Customer Review (2025)
British Gas
UK’s oldest and largest supplier
Wide network, energy + boiler services
⭐ 4.2/5 (Trustpilot: 4.1)
E.ON Next
Formerly E.ON + npower, focused on renewables
Tailored tariffs, business energy tools
⭐ 3.9/5 (Reviews.io: 1.2)
EDF Energy
French-owned firm, leading nuclear provider
Green tariffs, UK-based support
⭐ 4.1/5 (British Business Energy)
ScottishPower
Spanish-owned, focused on renewable electricity
Smart meter rollout, flexible tariffs
⭐ 4/5 (Which? 62%)
OVO Energy
Acquired SSE’s domestic arm in 2020
Innovative tech, strong carbon reduction ethos
⭐ 4.3/5 (Trustpilot: 4.4)
Octopus Energy
UK’s fastest-growing energy firm, tech-led and green
100% renewable, agile pricing models, great UX
⭐ 4.7/5 (Trustpilot: 4.8)
Are the Big Six Still Dominating the UK Market? Yes,but the landscape is stabilising after years of volatilit and right noW:
Over 85% of UK energy customers are with the top 10 suppliers
Smart meters and digital billing are now standard
Businesses prioritise renewable and net-zero aligned suppliers
For deeper market insight, see Ofgem’s latest supply market indicators:
What Are the Risks of a Dominated Market? A market led by a few major firms presents several risks:
🔻 Less price competition
With fewer players, the pressure to offer competitive rates reduces -— potentially leading to higher energy bills .
🌀 Reduced transparency
Large suppliers may trade wholesale energy internally, which can affect price fairness and public accountability.
💥 Greater shock impact
When major suppliers make pricing or operational changes, millions of customers are affected at once .
For economic context, see the UK Energy Research Centre’s market insights:
What Stops People Switching Energy Providers? Despite better switching tech and awareness, common myths still hold businesses back :
🚫 “Switching means new cables or meters” – False. Your infrastructure stays the same.
🚫 “I rent my property, so I can’t switch” – Not true. If you pay the bills, you can choose your supplier.
🚫 “It takes weeks to switch” – The average switch takes just 2–5 working days in 2025.
📢 TIP: Use your renewal window to compare deals and avoid being rolled into an expensive standard tariff, and For switching help and comparison tools, see Citizens Advice :
Should You Consider Smaller Suppliers? While the Big Six dominate, lots of smaller suppliers still play a vital role in the market.
✅ Advantages:
Personalised customer service
Innovative tariffs (like tme-of-use, a lot are EV-friendly)
Flexible contract options for SMEs
❌ Watch out for:
Financial resilience (check credit ratings and Ofgem approval)
Limited business support or account management features
Providers like Yü Energy , Pozitive Energy , and Ecotricity are gaining traction in 2025 thanks to strong niche offerings .
Recent Collapses of UK Energy Suppliers More than 30+ suppliers collapsed due to high wholesale prices and weak financial resilience.
Notable examples:
This reshaped the market into a more consolidated, tightly regulated environment.
2020
Yorkshire Energy: December 2020 – 74,000 customers (Scottish Power)
Tonik Energy: October 2020 – 130,000 customers (Scottish Power)
Effortless Energy: September 2020 – 2,500 customers (Octopus Energy)
GnERGY: March 2020 – 9,000 customers (Bulb Energy)
2021
Simplicity Energy: January 2021 – 50,000 customers (British Gas)
Green Network Energy: January 2021 – 360,000 customers (EDF Energy)
Hub Energy: August 2021 – 15,000 customers (E.ON Next)
Utility Point: September 2021 – 220,000 customers (EDF Energy)
People’s Energy: September 2021 – 350,000 customers (British Gas)
PFP Energy: September 2021 – 85,000 customers (British Gas)
MoneyPlus Energy: September 2021 – 9,000 customers (British Gas)
Avro Energy: September 2021 – 580,000 customers (Octopus Energy)
Green Supplier: September 2021 – 255,000 customers (Shell Energy)
Igloo Energy: September 2021 – 179,000 customers (E.ON Next)
Symbio Energy: September 2021 – 48,000 customers (E.ON Next)
Enstroga: September 2021 – 6,000 customers (E.ON Next)
Pure Planet: October 2021 – 235,000 customers (Shell Energy)
Colorado Energy: October 2021 – 15,000 customers (Shell Energy)
Daligas: October 2021 – 9,000 customers (Shell Energy)
Goto Energy: October 2021 – 22,000 customers (Shell Energy)
Bluegreen Energy: November 2021 – 5,900 customers (British Gas)
MA Energy: November 2021 – 300 business customers (SmartestEnergy Business)
Ampoweruk: November 2021 – 2,600 customers (Yü Energy)
Omni Energy: November 2021 – 6,000 customers (Utilita)
Zebra Power: November 2021 – 14,800 customers (British Gas)
CNG Energy: November 2021 – 41,000 business customers (Pozitive Energy)
Neon Reef: November 2021 – 30,000 customers (British Gas)
Social Energy: November 2021 – 5,500 customers (British Gas)
Orbit Energy: November 2021 – 65,000 customers (Scottish Power)
Entice Energy: November 2021 – 5,400 customers (Scottish Power)
Bulb: November 2021 – 1,700,000 customers (Special administration)
Zog Energy: December 2021 – 11,700 customers (EDF Energy)
2022
Whoop Energy: January 2022 – 2,000 customers (ScottishPower)
Together Energy: January 2022 – 176,000 customers (British Gas)
2023
Curo Energy: February 2023 – 4,000 customers (Octopus Energy)
Liberty Energy: March 2023 – 6,000 customers (EDF Energy)
Neon Energy: April 2023 – 8,000 customers (E.ON Next)
Rainbow Energy: May 2023 – 5,000 customers (Shell Energy)
Sunshine Energy: July 2023 – 7,500 customers (British Gas)
The collapse of these suppliers has affected millions of customers across the UK, highlighting the instability in the energy market.
🔚 Final Thoughts In 2025, the UK’s Big Six energy suppliers still dominate , but consumer power is growing . Whether you run a business or manage a household, don’t let legacy brand names or loyalty prevent you from comparing better tariffs.
Switching is simple, safe, and can lead to big savings.
Key Takeaways
✅ The Big Six in 2025:
British Gas, EDF, E.ON Next, Octopus, OVO, ScottishPower
✅ The market is more stable after 30+ supplier collapses
✅ Switching is fast (2-5 days) and simple
✅ Smaller suppliers offer innovation and personalised service
✅ Businesses increasingly choose renewable-focused providers
FAQs for the Big Six Energy Suppliers 1. Who are the Big Six energy suppliers in 2025?
The current Big Six in 2025 are British Gas, EDF Energy, E.ON Next, Octopus Energy, OVO Energy and ScottishPower. These suppliers now hold the majority share of UK energy customers following years of market consolidation.
2. Why did the Big Six change from the original group?
The original Big Six (British Gas, EDF, E.ON, npower, SSE and ScottishPower) changed due to mergers and acquisitions. npower was absorbed by E.ON, and SSE’s domestic customer base was acquired by OVO, which reshaped the top six suppliers.
3. Are the Big Six always the cheapest energy suppliers?
Not always. While they offer stability and a wide range of tariffs, smaller suppliers can sometimes provide cheaper or more innovative deals. It’s always worth comparing prices before renewing your tariff.
4. Is it safe to switch away from a Big Six supplier?
Yes. Ofgem’s regulations ensure that switching is safe and your energy supply will not be interrupted and even if your new supplier fails, your energy continues under the Supplier of Last Resort (SoLR) process.
5. How long does it take to switch energy supplier in 2025?
Switching now typically takes 2-5 working days thanks to faster switching rules introduced by Ofgem.
6. Do I need new cables or a new meter to switch supplier?
No. Your physical infrastructure stays the same and switching only changes who bills you for your usage.
7. Why have so many UK energy suppliers collapsed?
Between 2020 and 2023, wholesale price spikes, poor financial resilience and weak hedging strategies caused more than 30 suppliers to go bust, leading to a more consolidated market dominated by stronger firms.
8. Are smaller energy suppliers a good alternative to the Big Six?
They can be as smaller providers often offer personalised support, competitive tariffs and green-focused plans. However, it’s essential to check financial stability and customer reviews before switching.
9. What factors should businesses consider when choosing an energy supplier?
You should look at contract length, unit rates, standing charges, renewable options, customer reviews, billing tools, and whether the supplier offers dedicated business support.
10. Will the Big Six change again in the future?
Possibly. The UK energy market continues to evolve, with mergers, regulatory changes and the growth of green suppliers and while the Big Six model remains relevant today, future consolidation or new entrants could reshape the list again.
Related Business Energy Guides Compare & Switching Guides Sector-Specific Energy Guides Tariffs, Pricing & Market Explained Meters, Technical & Admin Guides Green & Renewable Energy Options Major UK Business Energy Suppliers Cost Reduction & Strategy Market & Government Updates Hi, I’m Ally Cox , a senior copywriter and blogger at CompareYourBusinessCosts.co.uk, the UK’s trusted platform for comparing business services.over a decade of experience in the B2B sector, I specialise in simplifying complex topics like leased lines, VoIP, business energy, HR and payroll solutions, accounting software, and EPOS systems .HR, copywriting, and business operations- from clocking-in systems to card machines and office technology .informed, confident decisions when choosing products and services that improve efficiency and save money.
