The UK's best and worst pay-monthly mobile firms based on complaints

O2 customers had to make the most complaints to the regulator for the second quarter in a row, latest figures show.

New quarterly figures from the telecoms watchdog have revealed the companies faring the best and worst in terms of customer complaints.

There was a remarkable four-way tie among companies generating the lowest number of gripes, with Sky, Tesco, EE and Vodafone all sharing the top spot in the table

Conversely, O2 finished bottom of the pile for the second quarter running, racking up more than double the industry average number of complaints in the process.

According to Ofcom, the most common gripes it fielded related to O2's poor complaints handling (29%), service issues (25%) and billing problems (21%).

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Total complaints figures far higher

The graphic from Ofcom below highlights how all the major networks compare and covers the three months between October and December 2023, which are the latest figures available.

It's worth pointing out that, while the number of complaints appears low for all mobile providers, these are issues that customers have needed to escalate to Ofcom as they've been unable to resolve their issues directly with their provider. 

The actual number of complaints made directly to network providers is far higher: Ofcom's data suggests that more than one in eight (12%) mobile customers said they had a reason to complain over the last 12-month period. 

Best & worst mobile firms: complaints per 100,000 customers

As mentioned, Sky Mobile, EE, Tesco and Vodafone all generated just two official complaints per 100,000 customers, putting them top of the pile.

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Next on the list were BT Mobile and iD Mobile with a total of three complaints per 100,000 customers each, which is also the industry average.

That represents a relatively strong result for BT Mobile, given that the firm has been responsible for the highest number of complaints in four of the last six quarters.

At the bottom of the table, O2 was responsible for seven complaints per 100,000. 

This is the highest among all the major firms and more than double the industry average.

Which providers offer consistently good service?

Ofcom publishes data on the number of complaints it receives about each of the big telecoms providers every three months.

Looking at such a short period can be unreliable – any provider can have a temporary problem that dramatically skews the figures.

In order to give you a clearer picture of how the mobile network giants consistently fare, we've listed the complaints figures for the last six quarters (18 months) in the table below.

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Complaints per 100,000 customers over the last 18 months

*Ofcom did not publish data for Virgin in these quarters

Mobile coverage

Practically speaking, the most important thing to keep in mind when signing up for any phone contract is the coverage and reception offered by the operator (you can read about the best networks for signal and speed here).

Ultimately, an extremely helpful call centre is of little use if you can't even phone them in the first place!

To make sure you don't live in a particular network's 'blackspot', the links below will take you to each network’s coverage map or coverage checker, so you can get a decent idea of the coverage you can expect where you live.

• EE
• O2
• Three
• Talkmobile
• TalkTalk
• Tesco Mobile
• Virgin Mobile
• Vodafone
• iD Mobile

Finally, find out which other telecoms providers you should be dodging by reading our regularly updated roundups of The UK’s worst pay TV providers, The UK's worst home phone providers and The UK’s worst broadband providers.

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This article contains affiliate links, which means we may receive a commission on any sales of products or services we write about. This article was written completely independently.

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