Two things determine whether a household is well served by its energy supplier over the life of an account: whether the price is right for the tariff signed, and whether the supplier handles service, billing and complaints competently when something goes wrong. Price is a decision made at the tariff level, one deal at a time. Service is a supplier-level trait that persists across tariffs, and the two most credible measures of it are both published by regulators.
This page ranks eight of the largest UK dual fuel brands on those two regulator-published measures: the Citizens Advice quarterly domestic supplier star rating (Q1 2026, January-March) and Ofgem's complaints per 100 customer accounts (Q3 2025, from the January 2026 State of the Market Report). Each measure carries 20 of the 100 possible points in the SwitchPilot Score, so together they cover 40 points. The remaining 60 points cover price, price certainty and freedom to leave, all of which live on the SwitchPilot tariff tracker with live rates.
The order that emerges is not the one the cheapest-deal tables suggest. Two brands pull clear of the pack, four bunch tightly in the middle, and one household name lands at the bottom.
How this table works
The SwitchPilot Score, in full. The SwitchPilot Score assesses every energy deal on five factors: price (45%), Citizens Advice star rating (20%), Ofgem complaints record (20%), price certainty (10%), and freedom to leave / exit fees (5%). Three of those factors (price, price certainty, freedom to leave) are tariff-specific and depend on the deal a household signs. They live with live rates on the SwitchPilot tariff tracker.
This page shows only the two supplier-level service factors of the Score - the Citizens Advice quarterly star rating and Ofgem's complaints per 100 customer accounts. Together they are worth 40 of the 100 possible points, applied at the supplier level rather than the tariff level. For the full 100-point Score against any deal you can switch to today, use the tracker.
Both service measures draw on the same regulated complaints pipeline. The Citizens Advice star rating standardises complaint volume alongside call wait times, billing accuracy and complaint resolution speed. Ofgem's per-100-accounts figure captures raw complaint volume. Weighting each at 50% of the two-factor total (equivalent to 20% + 20% of the full SwitchPilot Score) is a faithful reflection of how the Score itself treats them.
Citizens Advice quarterly star rating
Period: Q1 2026 (January-March 2026).
Source: Citizens Advice domestic supplier league table, published on citizensadvice.org.uk. Scored 1-5. Weights complaint volume, contact wait times, billing accuracy and complaint resolution speed. Underlying data is reported by suppliers to Ofgem. Suppliers with fewer than 25,000 customer accounts are excluded.
Ofgem complaints per 100 customer accounts
Period: Q3 2025 (July-September 2025).
Source: Ofgem State of the Market Report, January 2026 (page 14). Lower is better. Q3 2025 industry range ran from 0.01 (Outfox, best) to 2.2 (Tru Energy, worst); industry average 0.9.
The two-service-factor table for 2026
The table below scores eight of the largest UK dual fuel suppliers on the two supplier-level service factors that feed the SwitchPilot Score. The Citizens Advice column shows each supplier's Q1 2026 quarterly star rating (out of 5, from the January-March 2026 domestic supplier league table). The Ofgem column shows complaints per 100 customer accounts for Q3 2025, as published in the Ofgem State of the Market Report (January 2026, page 14). Each factor is worth 20 points; the two together account for 40 of the SwitchPilot Score's 100 possible points.
How suppliers score on the two service factors of the SwitchPilot Score: Citizens Advice rating and Ofgem complaints
Each factor is worth 20 points of the full 100-point SwitchPilot Score. CA points = rating/5 × 20. Ofgem points = 20 × (2.2 - value) / 2.19, normalised against Ofgem's Q3 2025 industry range (0.01 best, 2.2 worst). Total is out of 40. The remaining 60 points (price, price certainty, freedom to leave) are tariff-level - see the SwitchPilot tariff tracker.
| Rank | Supplier | Citizens Advice (/5) Q1 2026 |
CA points (/20) | Ofgem / 100 accts Q3 2025 |
Ofgem points (/20) | Service factors (/40) |
|---|---|---|---|---|---|---|
| 1 | Octopus Energy | 3.67 | 14.7 | 0.6 | 14.6 | |
| 2 | E.ON Next | 3.71 | 14.8 | 0.9 | 11.9 | |
| 3 | EDF Energy | 2.90 | 11.6 | 1.2 | 9.1 | |
| 4 | So Energy | 2.86 | 11.4 | 1.3 | 8.2 | |
| 5 | OVO Energy | 3.30 | 13.2 | 1.5 | 6.4 | |
| 6 | British Gas | 2.61 | 10.4 | 1.2 | 9.1 | |
| 7 | Scottish Power | 2.94 | 11.8 | 1.4 | 7.3 | |
| 8 | Utility Warehouse | 2.45 | 9.8 | 1.6 | 5.5 |
Insufficient data: Fuse Energy is not scored in this table. Both Citizens Advice and Ofgem exclude suppliers with fewer than 25,000 customer accounts from their public quarterly reporting, and Fuse currently sits below that threshold. As its customer base grows past 25,000 it will enter both datasets and can be added to this table.
Where the two service factors agree - and where they diverge
The two factors are not perfectly correlated even though both draw on Ofgem-reported complaints. The Citizens Advice star rating weights how well complaints are handled (wait times, billing accuracy, resolution speed), while the Ofgem per-100 figure captures raw volume. A supplier can post a middling volume and still score respectably on Citizens Advice if it handles those complaints well - and vice versa.
| Supplier | Citizens Advice (Q1 2026) | Ofgem / 100 (Q3 2025) | Reading |
|---|---|---|---|
| OVO Energy | 3.30 (mid) | 1.5 (worse than average) | CA credits complaint handling; Ofgem penalises volume |
| Scottish Power | 2.94 (mid-low) | 1.4 (worse than average) | Both measures agree - middle of the pack |
| Utility Warehouse | 2.45 (low) | 1.6 (worst in set) | Both measures agree - bottom of the pack |
| British Gas | 2.61 (low) | 1.2 (matches EDF) | CA marks it down; Ofgem is closer to average |
| Octopus Energy | 3.67 (top of set) | 0.6 (well below average) | Both measures agree - top of the pack |
OVO is the most interesting divergence in the current set. Its Citizens Advice rating of 3.30 is mid-tier - materially better than British Gas or Utility Warehouse - because CA rewards the parts of the operation it handles well (contact and resolution). But Ofgem's raw complaint volume figure of 1.5 per 100 accounts sits well above the industry average of 0.9, and that drags its total down. Utility Warehouse is the opposite story: both measures land at the bottom of the set, so the total lands there too. There is no favourable measure to lift its score.
Octopus Energy dual fuel: top of both service measures
Octopus Energy leads the set with 29.3 out of 40, and it is the only supplier in the eight to hold both the lowest Ofgem complaint rate (0.6) and the second-highest Citizens Advice star rating (3.67). 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 what both the Ofgem volume figure and the Citizens Advice handling metrics reward. Our Octopus Energy review finds the same pattern across every quarter since 2022.
E.ON Next: highest Citizens Advice rating in the set
E.ON Next lands second with 26.7 out of 40, and its Citizens Advice rating of 3.71 is actually the highest in the eight - fractionally ahead of Octopus. Its Ofgem complaint rate (0.9 per 100 accounts) sits exactly at the industry average, which is what pulls its total behind Octopus's, but the operational discipline shown by the Citizens Advice score puts it clear of the rest of the field.
The bunched middle: EDF, So Energy, OVO, British Gas, Scottish Power
The middle five suppliers all sit between 19.1 and 20.7 out of 40, within two points of each other. That tight bunching reflects a market where none of the traditional large brands post standout service records, but none post collapses either.
Within that band, EDF, So Energy and British Gas land in similar territory because their Ofgem complaint rates cluster around the average (1.2 to 1.3 per 100 accounts), and their Citizens Advice ratings all sit between 2.6 and 2.9. OVO and Scottish Power are close behind, held up by respectable Citizens Advice scores despite worse-than-average complaint volumes.
Utility Warehouse: bottom of the eight
Utility Warehouse lands last on 15.3 out of 40. Both measures agree: it holds the worst Ofgem complaint rate in the set (1.6 per 100 accounts, well above the industry average of 0.9), and its Citizens Advice star rating of 2.45 is the lowest of the eight (rank 14 of 16 in the full Citizens Advice table). There is no divergence story here - the two service factors point in the same direction.
Worth knowing: the cheapest headline dual fuel tariff in any given week frequently comes from a brand in the bottom half of this table. Price is the largest single factor in the SwitchPilot Score, so a low headline rate can still produce a strong overall Score - but only against a specific tariff. Check the full 100-point Score for the deal you are considering on the SwitchPilot tariff tracker before signing.
Which dual fuel supplier scores best on service in 2026
On the two service factors of the SwitchPilot Score, Octopus Energy and E.ON Next pull clear of the pack. Both brands post above-average Citizens Advice ratings paired with at- or below-average Ofgem complaint rates. Nobody else in the eight combines both.
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: service and price are separate questions. A cheap dual fuel tariff from a bottom-half supplier can cost more in wasted hours than it saves in pounds, but that trade-off only matters against a specific deal. This table settles the service half. For the price half, and for the full 100-point SwitchPilot Score against any deal you can switch to today, use the tariff tracker.
Frequently asked questions
How does SwitchInsights score dual fuel suppliers in this table?
This table scores suppliers on the two service factors of the SwitchPilot Score: the Citizens Advice quarterly star rating and Ofgem's complaints per 100 customer accounts. Each factor is worth 20 points, so the two together account for 40 of the SwitchPilot Score's 100 possible points. The remaining 60 points cover price, price certainty and freedom to leave, all of which are tariff-specific and live on the SwitchPilot tariff tracker.
Why doesn't this table include price?
Price and price-certainty depend on the specific tariff a household chooses, not the supplier as a whole. A supplier can offer a market-leading fixed deal and a mediocre standard variable tariff at the same time. The SwitchPilot tariff tracker applies the full 100-point Score against the live rates of every eligible deal, which is where the price component belongs.
What is the SwitchPilot Score?
The SwitchPilot Score scores every UK energy deal out of 100 across five factors: price (45%), Citizens Advice star rating (20%), Ofgem complaints record (20%), price certainty (10%), and freedom to leave or exit fees (5%). Where a supplier or tariff has no public data on a factor, that factor is capped at zero for scoring purposes rather than re-weighted.
What is the Citizens Advice supplier star rating?
Citizens Advice publishes a quarterly domestic supplier star rating from 1 to 5, weighting complaint volume, contact wait times, billing accuracy and complaint resolution speed. It draws on complaints data suppliers report directly to Ofgem. Suppliers with fewer than 25,000 customer accounts are excluded.
What is Ofgem's complaints per 100 customer accounts figure?
Ofgem publishes the number of complaints each licensed supplier reports each quarter, normalised as complaints per 100 customer accounts. Lower is better. The Q3 2025 figures used here appear in the Ofgem State of the Market Report, published January 2026 (page 14), with an industry range that ran from 0.01 (Outfox, best) to 2.2 (Tru Energy, worst) and an industry average of 0.9.
Which dual fuel suppliers top the service factors in 2026?
Octopus Energy leads with 29.3 out of 40 available points, driven by a Q1 2026 Citizens Advice rating of 3.67 and a Q3 2025 Ofgem complaint rate of 0.6 per 100 accounts. E.ON Next follows at 26.7 out of 40, with the highest Citizens Advice rating in the set (3.71). The rest of the field bunches between 15 and 21.
Why isn't Fuse Energy scored in this table?
Fuse Energy sits below the 25,000-account threshold that Citizens Advice and Ofgem use to include a supplier in their quarterly public reporting. Because both service factors depend on those published datasets, Fuse is shown as insufficient data rather than scored.