The short version
Octopus comes out on top among large UK suppliers on most measures. Complaints are the lowest among major providers. The Kraken billing platform makes account changes fast. The tariff range is the most innovative in the market, especially for EV drivers and flexible households.
Octopus has earned its 4.8-star Trustpilot score from 728,000 reviewers, 90% of them five-star. There are two things worth knowing here. Intelligent Octopus Go works with a specific list of EVs and chargers. And in April 2026, Octopus updated the Intelligent Go unit rate with around ten days' notice. The standard variable tariff gets the usual 30.
What is Octopus Energy?
Greg Jackson founded Octopus Energy in 2016. Octopus built the Kraken platform from scratch as a single system for billing, tariffs, and smart-meter dispatch. Octopus now licenses Kraken to EDF, E.ON Next and others. Over 60 million customer accounts run on Kraken globally, with around 6.5 million on Octopus Energy UK supply.
From start-up to the UK's largest supplier
2016Founded with a piece of software and no customers
Greg Jackson sets up Octopus Energy in London. Octopus Investments backs the launch. Kraken goes live as the core operating platform. The six largest suppliers still hold around 85% of the domestic market.
2022Bulb's 1.5m customers join Octopus
The 2021-22 energy crisis collapses around 30 UK suppliers. Octopus acquires Bulb's 1.5m customers from the Special Administration Regime. Tokyo Gas invests $855m, valuing Octopus at $9.7bn.
2024Overtakes British Gas
Octopus passes British Gas in electricity customer numbers. No challenger supplier had ever held the top spot in UK energy retail before.
Octopus Energy tariffs and prices in 2026
Octopus Energy offers the widest tariff range of any major UK supplier. Flexible Octopus is the standard variable tariff and tracks the Ofgem cap each quarter. The rest are time-of-use tariffs aimed at EV drivers, heat pump homes, and solar households. Each smart tariff needs a smart meter installed with half-hourly settlement.
| Tariff | Type | Key rate / feature | Best for |
|---|---|---|---|
| Flexible Octopus | Variable | Tracks Ofgem cap: 24.5p/kWh elec, 5.74p/kWh gas (Q2 2026) | Cap-rate pricing, no lock-in |
| Intelligent Octopus Go | EV Smart | 7.5p/kWh for 6 hrs overnight (Kraken-scheduled); rising 1 May 2026 | EV drivers with a compatible car + charger |
| Octopus Go | EV | Off-peak 00:30-04:30 daily; any EV; no smart dispatch | EVs not on the Intelligent Go list |
| Agile Octopus | Wholesale | Tracks half-hourly wholesale prices; can go negative overnight | Flexible households shifting consumption to cheap windows |
| Cosy Octopus | Heat pump | Free electricity 04:00-07:00 and 13:00-16:00 daily | Heat pump households with a smart meter |
| Octopus Flux | Solar + Battery | Three-tier import + premium peak export rates | Solar and home battery households |
The standout is Intelligent Octopus Go. At 7.5p/kWh (rising 1 May 2026), the rate ranks as the cheapest EV tariff in the UK for overnight charging. It undercuts British Gas EV Power, OVO Drive, and E.ON Drive.
Kraken schedules charging automatically inside the cheap window. Drivers with electric cars get six hours of low-rate electricity without managing it, which saves money on every charge.
Which cars work: Intelligent Go works with most major EVs. The list includes Tesla, VW Group, BMW, Mercedes, Nissan Leaf, and Jaguar i-Pace, plus a smart home charger. Cars outside the list can use standard Octopus Go instead. Octopus expands the list regularly as new cars come online.
The April 2026 Intelligent Go rate update
In April 2026, Octopus updated the Intelligent Go unit rate with around ten days' notice. Octopus cited movements in wholesale energy markets linked to events in the Middle East. Smart tariffs are variable products by design, which gives Octopus room to keep off-peak rates sharp when markets shift.
On notice periods: Ofgem normally asks suppliers to give 30 days' notice on variable tariffs. The May 2026 update gave around ten. Customers can raise the notice with Octopus first. If it isn't sorted within 8 weeks, the Energy Ombudsman can step in. See our energy complaint guide.
Octopus Energy customer service
Citizens Advice scorecard and customer reviews: Octopus ranks among the top two or three suppliers in the UK. The scorecard measures complaints, call waiting, billing, switching, and support for vulnerable customers. Octopus Energy Trustpilot reviews stand at 4.8 stars from 728,000+ customers, the highest of any major UK energy supplier. Octopus agents have full account access, so most queries finish on the first call.
Octopus Energy pros and cons
What works
- Best Trustpilot-rated major energy supplier in the UK (4.8 stars from 728,000+ reviews)
- Lowest complaints volume among major UK suppliers, year after year
- Octopus Energy EV tariffs (Intelligent Go and Octopus Go) - cheapest mainstream EV charging rates in the UK
- Agile Octopus can return near-zero or negative unit rates overnight
- Kraken platform gives agents full account visibility, so most queries finish in one call
- 100% renewable electricity on every residential tariff
- Which? Recommended Provider for 9 years in a row
- Cosy Octopus, the strongest heat pump tariff in the UK, with up to 7 free hours of electricity daily
Worth knowing
- Intelligent Go works with a specific list of EVs; non-listed cars can use standard Octopus Go
- April 2026 Intelligent Go rate update came with around ten days' notice
- Home emergency cover is run by partner services, not an in-house engineer network
- Agile rewards households that actively shift use to cheap windows
Should I switch to Octopus Energy?
Octopus is the obvious pick for households with an electric car and a compatible smart charger. Even after the May 2026 rate update, Intelligent Go is much cheaper than the cap, and saves money on every overnight charge. Agile suits flexible households willing to shift dishwasher and battery use to cheap windows.
If you have no EV, no solar, and standard usage, Flexible Octopus tracks the cap. The customer service is the best in the market. Compare the market before deciding.
Frequently asked questions
Is Octopus Energy any good in 2026?
Yes. Octopus is widely seen as the best energy supplier in the UK for 2026 on the measures that matter: complaints, billing, customer service, and tariff innovation.
Octopus has been a Which? Recommended Provider for nine years in a row. No other large supplier has matched that. Octopus Energy Trustpilot reviews stand at 4.8 from 728,000+ customers, the highest rating of any major UK energy supplier.
Is Octopus Energy cheap?
Flexible Octopus tracks the Ofgem cap, which puts Octopus Energy prices in line with most large suppliers on the standard variable tariff.
Octopus stands out on smart tariffs. Intelligent Octopus Go is the cheapest EV tariff in the UK for overnight charging. Cosy Octopus gives heat pump homes up to 7 hours of free electricity daily. Agile Octopus can return near-zero unit rates overnight.
Octopus Energy vs British Gas: which is better?
Octopus is comfortably ahead on customer service, app experience, smart tariff range, and renewable supply. British Gas leads on HomeCare engineering cover and the Hive smart home range. For price, service, and a digital-first experience, Octopus is the stronger choice.
What is Intelligent Octopus Go?
Intelligent Octopus Go is the Octopus Energy EV tariff with a six-hour off-peak window overnight. Kraken schedules charging automatically inside the cheap window. The tariff ranks as the cheapest mainstream smart EV tariff in the UK. The list of supported electric cars covers most major models, and Octopus expands it as new cars come online.
How do I switch to Octopus Energy?
Switching to Octopus Energy takes around five working days. Octopus handles the move with your old supplier, and your supply does not get cut off at any point. Run the numbers against the wider market on SwitchPilot's tariff tracker first to make sure Octopus is the right move for your usage.
Is Octopus Energy 100% renewable?
Yes. Octopus matches every residential electricity tariff to 100% renewable energy under the REGO scheme. Octopus also runs its own wind and solar generation. British Gas's standard fuel mix is around 20% renewable for comparison.