What is Octopus Energy?

Octopus Energy is a UK energy supplier that launched in 2016. They supply gas and electricity to homes across Britain, just like British Gas, EDF or any of the other big names. The difference is in how they do it.

The basics

You sign up, they supply your gas and electricity, you pay a monthly bill. On the surface it works exactly like every other energy company. Your energy comes through the same pipes and wires regardless of who supplies it. Switching to Octopus doesn’t mean someone comes round to change anything physical.

What sets them apart is the technology behind it. Octopus built their own platform (called Kraken) from scratch rather than using the legacy billing systems that most energy companies still rely on. This matters because it lets them do things the old suppliers struggle with, like offering half-hourly variable pricing or smart EV charging schedules.

Why people switch

There are a few common reasons:

• Price: Octopus typically charges at or below the Ofgem price cap on their standard tariff. The big six suppliers tend to charge right at the cap.
• Smart tariffs: No other supplier offers the range of time-of-use tariffs that Octopus does. Agile, Go, Intelligent Go, Tracker, Cosy, Flux. Each one is designed for a different type of household.
• Customer service: They consistently rank top for customer satisfaction. Their Trustpilot rating is around 4.8 out of 5 from over 700,000 reviews. That’s unusual for an energy company.
• No exit fees: Even their fixed tariffs typically have no exit fees. You can leave whenever you want.

The tariffs

This is where Octopus really stands out. Most suppliers give you one option: a flat rate per kWh, same price all day. Octopus offers that too (it’s called Flexible), but they also have tariffs that vary by time of day, track wholesale prices, or give you cheap electricity when demand is low.

The main ones:

• Flexible is the standard flat-rate tariff. Simple, competitive, no smart meter needed.
• Agile changes price every half hour based on wholesale costs. Cheap overnight, expensive at peak times.
• Go and Intelligent Go give you super-cheap electricity overnight, mainly aimed at EV owners.
• Tracker follows the daily wholesale price, so you see exactly what energy costs on any given day.
• Cosy is designed for heat pump owners, with cheap windows morning, afternoon and evening.
• Flux is for solar panel and battery owners, letting you buy cheap and export at peak rates.

Each tariff has its own detailed guide in the tariffs section.

Who owns them?

Octopus Energy Group is a private company. They’re not listed on the stock market. Major investors include Origin Energy, CPP Investments, Tokyo Gas and Generation Investment Management (a firm co-founded by Al Gore). They’ve expanded internationally and now serve over 10 million customers globally, licensing the Kraken platform to other energy companies.

In the UK, they’ve grown through a mix of organic switching and acquisitions. They took on Bulb’s 1.5 million customers in 2022 after that supplier collapsed, and acquired Shell Energy’s retail business in 2023, adding another 1.4 million households. As of late 2025, Octopus supplies around 7.7 million UK households, making them the country’s largest domestic energy supplier.

The Kraken platform

Kraken is the technology platform that runs everything. Billing, customer service, smart tariff management, grid balancing. Octopus licenses it to other energy companies around the world, which is actually a significant part of their business.

For customers, Kraken means things generally work. The app is responsive, billing is accurate, and when they launch a new tariff it tends to work properly from day one. This sounds like a low bar, but if you’ve ever dealt with billing errors from a legacy supplier, you’ll appreciate it.

Is it right for everyone?

Octopus is a strong choice for most households, particularly if you have a smart meter, an EV, solar panels or a heat pump. The smart tariffs can save significant money if your situation fits one of them.

If you just want a simple, reliable energy supplier with good customer service and competitive pricing, their Flexible tariff does that without any complexity.

The main reason not to switch would be if you’re currently on a fixed deal with another supplier that has exit fees, and the savings don’t justify paying those fees. Check the tariff comparison tool to see live rates for your area.