Over two million customers could leave O2 as trust in mobile providers plummets

Our latest research shows customers intend to abandon O2 after the network raised its annual price increases, while trust in networks in general has taken a hit.

In a nationally representative survey, we asked thousands of mobile customers about their views on the price increases, whether they are being treated fairly and what action Ofcom should take to rectify the situation. 

The results suggest that over two million customers could be set to leave O2 due to the hikes. And the move by O2 and other providers' price hikes this year has seen trust in mobile providers plummeting. 

90% of mobile customers think telecoms regulator Ofcom should take some action, whether that’s banning mid-contract increases entirely, investigating if existing rules have been broken, or fining networks. 

Read our guide to the best and worst UK mobile networks to find a provider that won’t raise your bill every year.

O2 customers planning to leave the network

In January, Ofcom banned mid-contract price increases calculated with inflation or percentages. The intention was to make contracts clearer for customers, so they would know how much they’d pay across the whole term at the start. However, within the new rules it appears that there is still space for networks to hit customers with unexpected increases.

O2 recently decided to raise its annual airtime price increase from £1.80 a month to £2.50, a hike of almost 40%, for new and existing customers. In accordance with the rules, O2 had to offer existing customers on fixed-term contracts a 30 day period where they could exit their contract penalty-free,  and we urged people to switch to save money and avoid the hikes.

O2 customers have been venting their frustrations, with many feeling exploited or that they were paying unnecessarily high bills even before the increases raise prices even further. 

Among our survey respondents with O2, 13% said they plan to switch during the 30 day window that opened when O2 increased prices. If that feeling is shared across O2's more than 15 million customers, it could mean more than two million leaving the provider to find better deals elsewhere. 

In addition, our survey indicates that many O2 customers affected by the recent mid-contract hikes may have already switched providers.

O2 has said of the rises 'We appreciate that price changes are never welcome, but we have been fully transparent with our customers about this change, writing directly to them and providing the right to exit without penalty if they wish.'

Browse the Sim-deals on offer at Which? Switch Mobile to see what's available, or check out our pick of the best Sim-only deals, where we highlight options starting at just £5 per month.

Trust in mobile providers takes a hit as result of hikes

We also asked people how they felt about the price hikes being imposed by providers and how trustworthy they think mobile networks are. Based on our results, 78% of UK adults believe it’s unfair for providers to increase prices beyond the original contract terms, while 79% of O2 customers thought the same. 

O2’s recent actions, alongside increased price hikes from other providers this year, have had a detrimental effect, with nearly half (49%) of customers in our survey telling us their trust has decreased after hearing about the price increases. O2 customers were more likely to say their trust had dropped, with the proportion rising to 58%.

Unfortunately it’s not just mobile users being hit by higher bills, as many of the major broadband providers are also putting up their annual price increases.

Consumers urge Ofcom to take action

We asked mobile customers what action they thought Ofcom should take in response to network price increases, and the response was overwhelmingly that something should be done:

• 41% said Ofcom should take stronger action to stop mobile providers from raising prices mid-contract.
• 23% said it should require providers to make all future contracts fixed-price with no mid-term increases.
• 17% wanted the regulator to investigate whether the companies have broken existing rules.
• and 9% said it should issue warnings or fines if rules have been breached.

Only 2% of people said no action should be taken as providers should be free to set their own prices, and 8% weren't sure. 

Rocio Concha, Which? Director of Policy and Advocacy, said: 'It's not surprising that millions of loyal customers say they will leave O2 after they announced higher-than-expected price hikes last month for both new and existing customers. 

'Our research shows O2 customers could make significant savings and get a better service elsewhere, so it could be worth switching if you can do so without penalty or you're out of contract. 

'O2's unexpected mid-contract price hikes risk creating the impression that operators can play fast and loose with Ofcom's rules and get away with it. The regulator must urgently review the rules on mid-contract price hikes to ensure they are fit for purpose, fair for consumers and not open to abuse by providers.'

What you can do if you’ve been hit by the hikes

If you’re out of contract or within a 30-day notice window where you can switch without exit fees, the process is simple. You don’t need to contact the provider or get stuck in long queues trying to call customer service. 

• Sim-only customers can switch easily to another provider and keep their number
• Customers with a phone and Sim contract can still switch the Sim contract, and either pay off the remaining balance for their device, or continue to pay for it with O2 as normal

All you need is a porting authorisation code (PAC), which you get with a text message. To switch and keep the same mobile number, text PAC to 65075. You should be sent a text within one minute, and the PAC lasts for 30 days. 

Give the PAC to your new provider, which has to complete the switch within one working day. 

Find out more in our guide on how to switch mobile provider.

Research note

Data is from a nationally representative online survey of 2,091 UK adults aged 18+ conducted between 14 to 17 November 2025. 393 adults were with O2 and responsible for paying the bill. 

Gross estimate for 'over 2 million figure': The number of O2 contract customers in the survey are 393. Of these, 13% said they plan to switch from O2 within 30 days after being made aware of O2’s mid contract price rises. Applied to O2’s 15,763,300 contract customers, published in O2’s Q3 2025 Earnings Release, we estimate 2,049,229 O2 customers in contract say they plan to switch away from O2 within the next 30 days since the MCPR announcement. This is an estimate based on people’s stated intentions, which may not always translate into action.