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25th April 2025 10:40 - Utilities

Recent research highlights the top and bottom energy suppliers in 2025, as voted for by customers in the UK: A recent survey has revealed the top UK energy providers based on detailed customer feedback and reveals their overall satisfaction across a range of suppliers.

The research, undertaken by Which? surveyed 11,984 members of the public between September and November 2024, as part of their annual energy satisfaction survey, to gain important insight into supplier performance and customer satisfaction. The survey covered 16 UK suppliers.

In addition to analysing the highest and lowest-scoring providers, based primarily on customer satisfaction and their likelihood to recommend, suppliers also received an assessment score, which measured their behind-the-scenes practices. The research analysed how suppliers performed against a set of fundamental customer metrics covering areas including support for customers who need it, ease of contacting, ease of switching and value for money.

To calculate the best-rated energy suppliers overall for 2025, customers were asked to rate ‘satisfaction with their supplier’ and their ‘likelihood to recommend.’ To create a fuller picture, the customer results were subsequently combined with the Which? assessment score, to calculate an overall aggregate for each supplier. The assessment score rated suppliers on the following key criteria with a maximum percentage rating for each domain: ease of contacting a supplier (25%), providing support for customers who need it (25%), dealing with complaints (30%), performance against their (2023) smart meter targets (10%) and switching (10%).  

Based on the customer survey, the top three suppliers in 2025, according to Which? were adjudged to be Octopus Energy (78%), 100Green (76%) and Utility Warehouse (73%). Ovo Energy (56%), Scottish Power (58%), and British Gas (61%) were bottom of the customer score table. When the customer results were combined with the Which? assessment score, Octopus Energy remained in first place (74%), and Utility Warehouse (73%) moved up to second. Utilita ranked third with a score of 71% in the combined rankings, even though it came joint eighth in the customer survey.

When customers were asked to provide star ratings (1-5) for various aspects of service, encouragingly, seven out of the 16 sixteen suppliers received four stars for value for money (Octopus, 100Green, Utility Warehouse, Sainsbury’s Energy, Good Energy, Co-op Energy and Outfox the Market). British Gas and Ovo Energy both managed just two stars. Octopus Energy, 100Green and Utility Warehouse each received five stars for customer service; however, British Gas, Ovo Energy, Scottish Power, and Outfox the Market all received two stars.

Emily Seymour, energy editor at Which?said: While some energy firms were found to be 'powering ahead of the competition, others are letting down their customers badly — and that’s unacceptable for such a vital service. Any firms falling short urgently need to up their game to ensure they are providing the service and value for money that consumers rightly expect from their energy supplier.”

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