O2 Network Review 2026: Coverage, Roaming, Priority Perks and Complaints Record

Ownership and where O2 sits in the UK market

O2 is the consumer mobile brand of Virgin Media O2, the joint venture created in 2021 when Telefonica's UK operation merged with Liberty Global's Virgin Media. That makes it one of the four companies that actually own mobile masts and spectrum in the UK, rather than renting capacity from someone else. Counting the virtual networks that run on its infrastructure, O2 carries more UK connections than any other operator.

That host role matters for consumers in a specific way: giffgaff, Sky Mobile and Tesco Mobile all use O2's radio network. A postcode that gets a strong O2 signal will get broadly the same signal on those brands, usually at a lower monthly price, though without some of O2's own perks and priority traffic management.

Coverage, 5G and the 3G switch-off

O2 reports 4G coverage reaching the large majority of the UK landmass and continues to expand 5G city coverage. As with every operator, headline percentages describe outdoor coverage; indoor signal depends on building materials and local mast placement, so the reliable test is Ofcom's independent coverage checker against a specific postcode rather than any provider's own map.

O2 completed its 3G switch-off in 2025. Older devices that rely on 3G for data no longer get online on the network, and calls on such devices fall back to 2G where available. Anyone with a handset more than roughly a decade old should confirm it supports 4G Calling before signing a new O2 contract.

Tariffs, Refresh contracts and Priority perks

O2's signature contract structure is Refresh, which splits the bill into a device plan and an airtime plan. When the device plan is paid off, that portion of the bill ends automatically, which avoids the classic trap of continuing to pay a handset subsidy after the phone is yours. SIM-only and pay-as-you-go options sit alongside it.

Priority is the perks scheme: presale access to O2 Academy and O2 arena tickets, rotating weekly offers, and airport lounge or venue benefits at intervals. For gig-goers the presale access alone can justify the brand choice; for everyone else it is a nice-to-have rather than a reason to pay more per month.

The roaming position is the standout. While most large UK providers reintroduced daily EU roaming charges after Brexit, O2 has continued to include EU roaming within a monthly fair-use data allowance on most plans. For anyone spending weeks per year in Europe, that difference compounds into a meaningful annual saving.

Customer service and the complaints record

The independent evidence to weigh is Ofcom's quarterly complaints league table, which counts complaints per 100,000 customers for each large provider. Across several recent quarters O2 has sat among the most complained-about of the network operators, with billing and service issues the recurring themes. That does not mean every customer has a poor experience, but it is the pattern the regulator's own data shows and the honest counterweight to the perks and roaming strengths.

Complaints that O2 cannot resolve within eight weeks, or that reach deadlock earlier, can be escalated free of charge to the alternative dispute resolution scheme O2 belongs to. Keeping a dated record of contacts makes that escalation far more effective.

Switching to or away from O2

Switching follows Ofcom's text-to-switch rules. Texting PAC to 65075 from the line being moved returns a porting code, valid for 30 days, that the new provider uses to move the number; texting STAC instead cancels without keeping the number. The losing provider must state any early-exit fees in the reply, so the true cost of leaving mid-contract is visible before committing.

Since Ofcom's rules took effect in early 2025, new contracts must state any mid-contract price rises in pounds and pence upfront rather than as an inflation formula, which makes O2's multi-year cost directly comparable against rivals at sign-up.

Frequently asked questions

Does O2 still include EU roaming?

On most current plans, yes: EU roaming is included within a monthly fair-use data allowance rather than charged at a daily rate. The allowance and covered countries are set out in each plan's terms, so the plan-specific limit is worth checking before travel.

Which other networks run on O2?

giffgaff, Sky Mobile and Tesco Mobile all use O2's radio network. Coverage at a given postcode is broadly the same on those brands, though speeds can be managed differently at peak times.

How do I leave O2 and keep my number?

Text PAC to 65075 from the O2 line. The reply contains a porting code valid for 30 days plus any early-termination charge. Give the code to the new provider and the number moves, usually within one working day.