Choosing a dual fuel supplier on price alone misses half the picture. The other half sits in two public datasets that most comparison pages ignore: Ofgem complaint data, which counts how often customers escalate a problem, and Trustpilot ratings, which capture how the public scores each brand. Read together, they separate the suppliers that run smoothly from the ones that look cheap until something goes wrong.
This league table answers one question directly: which dual fuel suppliers have the best ofgem and trustpilot ratings in 2026. SwitchInsights ranked eight of the largest dual fuel brands by combining both measures, then checked where the two sources agree and where they pull apart.
The order that emerges is not the one the cheapest-deal tables suggest. Two brands top both measures at once, while three household names many people treat as safe defaults sit in the bottom half.
How SwitchInsights scored this league table
How SwitchInsights built this dual fuel energy league table: every supplier is scored across two public measures, Ofgem complaint data weighted at 60% and customer ratings weighted at 40%, combined into a single service score out of 100. Customer ratings are sourced from Trustpilot and recorded in January 2026. We refresh the numbers whenever Ofgem or a supplier's customer-rating average moves, so the ranking stays close to lived experience.
Ofgem carries the heavier weight for a reason. A public review average is shaped by whoever chooses to write a review, whereas complaints reported to Ofgem reflect households unhappy enough to formally escalate.
Ofgem complaint data
Complaints reported by suppliers each quarter, expressed per 100,000 customer accounts. Lower is better. Cases escalated to the Energy Ombudsman carry more weight than a single call, so the figure tracks unresolved problems.
Customer ratings
The current public review average for each brand, sourced from Trustpilot and recorded in January 2026. Higher is better. We treat these ratings as a sentiment signal, not a precise metric, because the reviews skew toward recently switched customers.
What Ofgem complaint data measures
Standardising complaints per 100,000 customer accounts lets a supplier with two million customers be compared fairly against one with 200,000, and the same data feeds the Citizens Advice star rating and the Energy Ombudsman caseload. A rising rate is the clearest early warning that service is straining, and when energy supplier complaints uk figures climb they usually trace back to billing errors, slow refunds, or contact centres struggling with demand.
The dual fuel energy league table for 2026
The table below ranks the eight largest dual fuel energy suppliers 2026 shoppers are most likely to see, ordered by the combined service score. The Ofgem column shows complaints per 100,000 accounts for Q4 2025, and the customer-rating column the public review average from January 2026.
SwitchInsights dual fuel service ranking - 2026
Combined score weights Ofgem complaint data at 60% and customer ratings at 40%. Ofgem figures are complaints per 100,000 accounts for Q4 2025; customer ratings sourced from Trustpilot, recorded January 2026.
| Rank | Supplier | Ofgem complaints / 100k | Customer rating | Combined score |
|---|---|---|---|---|
| 1 | Octopus Energy | 1,890 | 4.8 | |
| 2 | Utility Warehouse | 1,540 | 4.6 | |
| 3 | So Energy | 2,470 | 4.5 | |
| 4 | E.ON Next | 3,900 | 4.5 | |
| 5 | EDF Energy | 5,180 | 4.8 | |
| 6 | British Gas | 5,940 | 4.3 | |
| 7 | OVO Energy | 6,720 | 4.6 | |
| 8 | Scottish Power | 7,610 | 4.3 |
Where Ofgem data and Trustpilot ratings disagree
The most useful part of any supplier comparison is where the sources contradict each other. A brand can hold a glowing Trustpilot average while quietly generating a heavy complaints load, because the two datasets sample different customers.
| Supplier | Customer rating | League rank | Reading |
|---|---|---|---|
| EDF Energy | 4.8 | 5th / 8 | Looks better than the complaints suggest |
| OVO Energy | 4.6 | 7th / 8 | Looks better than the complaints suggest |
| British Gas | 4.3 | 6th / 8 | Both measures point the same way |
| Octopus Energy | 4.8 | 1st / 8 | Consistent across both sources |
EDF Energy is the sharpest example. Its 4.8 Trustpilot rating sits alongside a complaint rate that places it mid-table, so a shopper who reads only the star score would overestimate the account. We treat that gap as a warning, not a contradiction, because the two figures measure different moments in the relationship.
Octopus Energy dual fuel: top of both tables
Octopus Energy dual fuel accounts lead the 2026 ranking, and they are the only large brand to hold a top-three complaints position and a 4.8 Trustpilot rating at the same time. That consistency is what separates it from the rest of the field, where a strong showing on one measure is usually offset by a weaker one.
Its Kraken billing platform is the main reason. Automated meter reads and faster refunds keep routine problems from turning into formal complaints, which is exactly what the Ofgem data rewards. Our Octopus Energy review finds the same pattern across every quarter since 2022.
E.ON Next dual fuel and So Energy: the quiet performers
E.ON Next dual fuel customers land fourth, and the brand is the strongest of the traditional large suppliers on complaints. Its 4.5 Trustpilot rating is unremarkable, yet its complaint rate near 3,900 per 100,000 accounts sits far below the legacy pack, which lifts its combined score.
So Energy takes third overall. As a smaller challenger it fields fewer accounts, but its low complaint rate and stable 4.5 Trustpilot rating give households a credible alternative without the service trade-off.
British Gas, EDF Energy and OVO Energy dual fuel: strong brands, weaker complaints
British Gas dual fuel sits sixth. It remains one of the largest suppliers by volume, yet its complaint rate near 5,940 per 100,000 accounts keeps it in the bottom half, and its 4.3 Trustpilot rating does little to help.
OVO Energy dual fuel ranks seventh, weighed down by the legacy SSE customers it absorbed in 2020 and the billing friction that followed. EDF Energy dual fuel finishes fifth, propped up by that high Trustpilot score even as its complaint rate drags it down. All three are competent brands, but the Ofgem numbers show why recognition is a poor guide to service.
Worth knowing: the cheapest headline dual fuel tariff in any given week frequently comes from a brand in the bottom half of this table. It pays to check the Ofgem complaint data before signing.
The best dual fuel supplier for customer service
If the priority is the best dual fuel supplier for customer service, the data points to Octopus Energy first and Utility Warehouse a close second, with So Energy and E.ON Next rounding out a strong top four. Those are the brands where a good Trustpilot rating is backed by low complaint volumes, not a favourable review mix, and for a shortlist of the best dual fuel energy suppliers uk households can switch to today the same four names dominate.
You can compare live prices for these brands on the SwitchPilot tariff tracker, then cross-check the winner here. For the numbers behind every supplier, see our full supplier complaints record.
Our take: price still matters, but a cheap dual fuel tariff from a bottom-half supplier can cost more in wasted hours than it saves in pounds. The suppliers that top both Ofgem complaint data and Trustpilot ratings give households a fair price and a quiet account at once, which is worth more than a marginal saving on the unit rate.
Frequently asked questions
Which dual fuel suppliers have the best Ofgem and Trustpilot ratings?
Octopus Energy and Utility Warehouse top both measures, pairing the lowest Ofgem complaint rates among large brands with strong Trustpilot ratings. So Energy and E.ON Next follow, while British Gas, OVO Energy and Scottish Power sit in the bottom half.
What is Ofgem complaint data and how is it measured?
Ofgem collects the complaints suppliers report each quarter, standardised as complaints per 100,000 customer accounts, so a lower figure means fewer households had to escalate. The measure also feeds the Citizens Advice star rating.
Are Trustpilot ratings reliable for comparing energy suppliers?
Trustpilot ratings are useful but self-selecting, because recently switched customers are often prompted to review while long-standing ones stay silent. A high average alongside a poor complaint rate signals reviews that capture the joining experience, not years of service.
Is Octopus Energy the best dual fuel supplier for service?
On combined public data, Octopus Energy dual fuel accounts lead the 2026 league table, holding a 4.8 Trustpilot rating alongside one of the lowest complaint rates of any large supplier. Utility Warehouse records marginally fewer complaints, so treat the two as closely matched.
Which dual fuel supplier has the worst complaints record?
Among the large brands here, Scottish Power records the highest Ofgem complaint rate at roughly 7,610 per 100,000 accounts as of Q4 2025, followed by OVO Energy. Both keep respectable Trustpilot ratings, which is why complaint data adds detail a star average conceals.
Is a dual fuel tariff cheaper than using two separate suppliers?
A dual fuel tariff bundles gas and electricity with one supplier and often carries a small discount, although the gap has narrowed since the energy crisis. The larger benefit is a single account and one complaints route when something goes wrong.
How often does SwitchInsights update the dual fuel energy league table?
We refresh the ranking whenever Ofgem publishes a new quarterly complaints report or a supplier's Trustpilot average moves. These figures reflect Ofgem data for Q4 2025 and Trustpilot ratings from January 2026.