Who is cheaper than Octopus Energy? (2026)

Affiliate disclosure: this post contains an Octopus Energy referral link. If you use it, both of us get £50 bill credit — the same £50 any Octopus referral earns, just attributed to me. It doesn't change the price you pay. I'm a six-year Octopus customer, so this isn't a neutral comparison; the supplier-by-supplier sections below are summarised from each company's published rates and the Cheap Energy Club analyses I run when comparison-shopping at switch points.

If you've Googled "is Octopus the cheapest energy supplier" the honest answer is: not always, and not by much. Octopus Energy is consistently competitive on price across the 2026 UK market, but it's not the rock-bottom supplier on any given tariff in any given week. There are usually one or two suppliers undercutting it on Fixed deals, and the smaller end of the market occasionally publishes headline rates that beat the Ofgem price cap by more than Octopus does.

This post walks through who actually undercuts Octopus in 2026, by how much, and what you give up to take the saving.

How UK energy pricing works in 2026

Before naming specific suppliers, the structural picture matters. Three things to keep in mind:

1. The Ofgem price cap regulates every standard variable tariff. From 1 April to 30 June 2026, the cap is £1,641 per year for a typical dual-fuel direct-debit household (electricity unit rate around 25p/kWh, standing charge 57.2p/day). Every supplier offering a default variable tariff is bound by that maximum. So when people talk about supplier A being "cheaper than" supplier B, what they usually mean is supplier A's Fixed deal undercuts supplier B's Fixed deal — not that the variable tariffs differ.

2. Fixed deals are where suppliers compete on price. A Fixed deal locks in the unit rate and standing charge for 12 (or sometimes 24) months. Suppliers price these against the next forecast price cap, plus a margin and a hedge against wholesale movement. The cheapest Fixed deal on the market changes quarter to quarter as wholesale prices and forecast caps shift.

3. Smart tariffs are where the biggest savings live — but only for the right households. Octopus Tracker has averaged around 20.7p/kWh in 2026 versus the price cap's ~26p/kWh — a 20%+ saving on the unit rate. Agile, Go, Intelligent Go and Cosy can save more for households that can shift load. None of Octopus's main competitors offer an equivalent smart-tariff range, which changes the "who's cheapest" question fundamentally if you're a candidate for a smart tariff.

With that in mind, here's the supplier-by-supplier comparison.

Who undercuts Octopus in 2026

The headline takeaway: on a price-only comparison, Octopus is rarely the absolute cheapest, but rarely far from it. The gap to the cheapest available Fixed deal in any given quarter is typically £30–£100 a year on typical dual-fuel usage. Smart-tariff households should be running a different comparison entirely.

So Energy

So Energy is owned by ESB Group (the Irish state-owned utility) and has built a reputation as a price-competitive challenger. Their Fixed deals are routinely a few percent below Octopus's Fixed in the weeks after each new price-cap publication. They have a credible app, decent customer-service ratings (though below Octopus on most polls), and the ESB ownership gives them more balance-sheet stability than the wave of failed pre-2022 challengers.

Where So Energy doesn't compete is the smart-tariff range. They don't offer anything equivalent to Octopus Tracker, Agile, Go, Intelligent Go or Cosy. So if you've got a smart meter and a household that could meaningfully save on a smart tariff, So Energy's Fixed-deal saving against Octopus is often less than what you'd save by being on the right Octopus smart tariff.

Verdict: worth a quote alongside Octopus at every switch point. Don't switch reflexively if their Fixed beats Octopus by £30 — factor in the smart-tariff path you're closing off.

Outfox the Market

Outfox the Market regularly publishes the cheapest headline Fixed deal in MoneySavingExpert's Cheap Energy Club analyses. Some quarters they undercut Octopus's Fixed by closer to £100/year on typical usage.

The trade-off is service quality. Outfox the Market's Trustpilot rating sits well below Octopus's 4.8/5 — typically around 3.5–4.0 — and their Which? customer satisfaction polling has been consistently below the major suppliers. Complaints tend to cluster around billing accuracy and customer-service responsiveness.

Verdict: worth a quote if your priority is rock-bottom price and you're willing to accept a higher chance of service friction. If a 25-minute phone wait would frustrate you, the £50–£100/year saving may not be worth it.

Utility Warehouse

Utility Warehouse operates a different model from the rest of the supplier market: a Discount Club where you bundle energy with broadband, mobile, and insurance, and the combined bill comes out below what you'd pay buying each service separately at best-buy rates. Standalone energy pricing isn't typically below Octopus's. The savings come from the bundle.

This works well if (a) you want to simplify your household admin to one bill from one provider, and (b) the broadband and mobile services UW offers cover your needs. It works less well if you want best-buy on each service — UW broadband isn't usually the fastest, UW mobile isn't usually the cheapest, and locking everything together limits your ability to switch any single service.

Verdict: worth a quote if you actively want to consolidate utilities. Skip if you're optimising service-by-service.

EDF

EDF is one of the Big Six legacy suppliers. Their Fixed deals occasionally undercut Octopus's, particularly on longer 24-month terms when EDF wants to lock in market share. Their Trustpilot score is genuinely good (4.8/5 — matching Octopus), though their broader Which? customer satisfaction polling tends to lag.

EDF has nothing equivalent to Octopus's smart-tariff range. Their EV tariff (GoElectric) competes on overnight rates but doesn't have the same load-shifting flexibility as Intelligent Octopus Go. Their Fixed range competes on simpler dual-fuel deals.

Verdict: worth a quote at every switch point alongside Octopus. If their Fixed beats Octopus's by enough to overcome the smart-tariff opportunity cost, switch. Otherwise stay.

E.ON Next

E.ON Next is the strongest legacy-supplier challenger to Octopus on the price-vs-service combination. Their service ratings are consistently among the best of the Big Six successors. The Which? 2026 energy survey put E.ON Next at 66% customer satisfaction, the best result among large suppliers (though without the Recommended Provider badge, which Octopus holds).

E.ON Next's Fixed deals typically sit close to Octopus's — sometimes a touch cheaper, sometimes a touch dearer. Their EV-specific tariffs (Next Drive, Next Drive Smart) are credible alternatives to Octopus Go. Their referral scheme pays a retail voucher (M&S, Sainsbury's, Argos and similar) rather than bill credit.

We've covered the head-to-head in depth in Octopus vs E.ON Next referral. Short version: it's a close call, with the smart-tariff range usually tipping it to Octopus for households that can use one.

Verdict: the most credible alternative to Octopus in the legacy-supplier space. Worth a quote.

OVO Energy

OVO absorbed SSE in 2020 and now sits as one of the larger UK suppliers. Their Fixed deal pricing tends to come in slightly above Octopus's on most quarters. Their service polling is mid-pack — better than British Gas, behind Octopus and E.ON Next.

OVO's interesting product is the Power Move reward scheme, which pays a flat-rate cashback for shifting electricity usage out of the 4–7pm peak window. It's simpler than Octopus Agile (no half-hourly pricing to track), but the savings ceiling is lower. For households who'd find Agile too admin-heavy but want some peak-shifting reward, Power Move is a reasonable middle ground.

Verdict: worth a quote if Power Move's simplicity appeals, but Octopus usually wins overall.

British Gas

British Gas pricing rarely undercuts Octopus on Fixed deals. Occasionally a 24-month Fixed matches Octopus's 12-month rate, but the differential is typically modest. British Gas's Trustpilot score sits at 4.4/5 — credible but below Octopus's 4.8/5 — and their Which? customer satisfaction polling has been consistently below the smarter challengers.

What British Gas has is the legacy comfort: nationwide service network, Homecare warranty add-ons, and brand recognition for households who want a household name. The smart-tariff range is much narrower than Octopus's.

Verdict: marginal. Quote at switch points but don't expect to win.

Where the smart-tariff comparison flips everything

The supplier-by-supplier table above assumes Fixed-tariff comparison. The picture changes substantially if you're a candidate for a smart tariff:

• EV at home → Intelligent Octopus Go. April 2026 off-peak rates dropped up to 39% across regions; some are now under 4p/kWh. Nothing in the rest of the UK supplier market matches this for whole-home overnight cheap power.
• Heat pump → Cosy Octopus. Eight off-peak hours a day at around 14.5p/kWh. No competitor has an equivalent heat-pump-specific tariff structure.
• Solar (no battery) → Outgoing Octopus for export, paired with whatever import tariff suits. Other suppliers offer export tariffs but Octopus's pairing flexibility is broader.
• Engaged switcher with no shiftable load → Octopus Tracker beats the price cap on average without requiring load-shifting. Closest competitor: Ovo's Power Move at a much smaller saving ceiling.

If any of those describe you, the "is Octopus the cheapest?" question isn't really the right one — the right one is "what's the cheapest tariff for my household across all suppliers?" and the answer is usually Octopus on the right tariff.

For everyone else — flat usage curve, no EV, no heat pump, no solar — the Fixed-vs-Fixed comparison is real, and the answer is some supplier may undercut Octopus by £30–£100/year. Which side of that line you sit on depends on how much weight you put on service ratings and the £50 referral credit.

My take after six years on Octopus

Disclosure: I've been an Octopus customer since September 2019. I've comparison-shopped at every tariff renewal and Octopus has been in the top three on price every time, never absolute cheapest. The gap to the cheapest available has typically been £40–£80/year on my usage. I've stayed because:

1. The service is the best I've experienced across four UK suppliers.
2. The smart-tariff range gives me future optionality (when I eventually buy an EV, the Octopus Go or Intelligent Octopus Go switch is a few clicks in the app).
3. The £50 referral credit through friends offsets roughly the price gap most years.

If those three things matter to you, Octopus probably wins overall. If your sole criterion is the cheapest Fixed deal on any given week, Outfox the Market or So Energy will more often top your comparison.

The fuller breakdown of the actual customer experience is in my Octopus Energy review after 6 years.

How to compare properly at your next switch

Three steps that beat any blog post:

1. Run a Cheap Energy Club quote. MoneySavingExpert's Cheap Energy Club is free and pulls live Fixed-deal pricing across most UK suppliers. It will tell you who's cheapest right now on your postcode and usage.
2. Check the smart-tariff angle. If you have an EV, heat pump, solar, or could move to one in the next year, calculate the smart-tariff saving against the cheapest Fixed deal. Octopus's tariff page has rate calculators.
3. Factor in service and switching cost. A £50 saving from a low-rated supplier that takes 25 minutes per phone call is often a false economy. A £100 saving from a credible challenger like So Energy or E.ON Next is worth taking seriously.

If the answer comes out as Octopus, you can use my Octopus £50 referral link — both of us get £50 bill credit, paid after your first direct debit. The full referral scheme is explained on the Octopus Energy referral page.

Cheaper than Octopus Energy FAQs

Is anyone genuinely cheaper than Octopus Energy in 2026?

Yes, on specific tariffs in specific weeks — but not consistently across a year. So Energy and Outfox the Market regularly publish Fixed deals a few percent under Octopus's, particularly in the weeks immediately after a new Ofgem price cap publication. Utility Warehouse can undercut on bundled multi-utility packages where you take broadband or mobile alongside energy. EDF, E.ON Next, and OVO each occasionally beat Octopus on a one-off Fixed deal. The catch: none of these consistently lead, and the gap is usually £30–£100 a year on typical usage — small enough that service quality, smart-tariff range, and the £50 referral often tip the maths back to Octopus.

What is the cheapest UK energy supplier in 2026?

There isn't a permanent cheapest UK energy supplier. The Ofgem price cap regulates every standard variable tariff to the same maximum (currently £1,641/year typical dual-fuel direct debit, 1 April – 30 June 2026), so the differences come from Fixed-deal pricing and smart tariffs. Across April 2026, the cheapest Fixed deals on MoneySavingExpert's Cheap Energy Club have rotated between Octopus, So Energy, Outfox the Market, EDF, and E.ON Next, depending on region and tariff term. Smart tariffs like Octopus Tracker and Agile have averaged around 20.7p/kWh — comfortably below the typical price-cap rate of around 26p/kWh.

Is So Energy cheaper than Octopus?

Sometimes — particularly on shorter Fixed terms. So Energy is owned by ESB Group and has built a reputation for keeping standard tariff rates competitive against the price cap. They've published Fixed deals a few percent below Octopus's Fixed in some 2026 quarters. But they don't currently match Octopus's smart-tariff range (no equivalent of Tracker, Agile, Go or Cosy), so the comparison is really 'cheaper Fixed deal vs broader tariff choice + better service ratings.' Worth comparing on a switch quote, not assuming.

Is Utility Warehouse cheaper than Octopus?

Only if you bundle. Utility Warehouse's standalone energy pricing isn't typically below Octopus's, but their multi-service Discount Club model — bundling energy with broadband, mobile, and insurance — produces a combined-bill saving that can beat Octopus on the total household number. The trade-off: you're locking in across multiple services, and if one underperforms (broadband speed, mobile coverage), you can't easily switch just that one. For households happy to consolidate everything with one provider, Utility Warehouse is worth a quote. For everyone else, Octopus on energy + best-buy on each other service usually wins.

Why is Octopus more expensive than some smaller suppliers?

Octopus prices to a sustainable margin rather than to win the cheapest-on-paper headline. Their balance sheet, customer-service costs, smart-tariff investment (Tracker, Agile, Go, Intelligent Go, Cosy all require ongoing engineering), and risk reserves get baked into the price. Smaller suppliers can run thinner margins to win market share, but the post-2021 supplier-failure cull (Bulb, Avro, Green, Utility Point and 30+ others) showed how that often ends. Octopus is consistently within a few pence per kWh of the cheapest available Fixed deal — close enough that for most households the price differential gets eaten by service quality, smart-tariff savings, or the £50 referral credit.

You might also like

• Octopus Energy review: 6 years as a customer
• Which Octopus Energy tariff is right for you?
• Octopus Energy vs E.ON Next referral: which gives you more?
• What does Martin Lewis say about Octopus Energy?

Sources

• Ofgem energy price cap (1 April – 30 June 2026): https://www.ofgem.gov.uk/information-consumers/energy-advice-households/energy-price-cap-explained
• MSE Cheap Energy Club: https://www.moneysavingexpert.com/utilities/cheap-energy-club/
• Octopus Tracker: https://octopus.energy/smart/tracker/
• Which? 2026 energy survey: https://www.which.co.uk/reviews/energy-companies/article/energy-companies/which-energy-survey-results-ajqM43e6ycY8
• Trustpilot scores referenced as of April–May 2026.

Rates and supplier comparisons accurate as of 4 May 2026. The Q3 2026 Ofgem price cap (effective 1 July) publishes by 27 May 2026 and may change the comparison.