O2 SIM Only Deals: Best Plans for November 2026

O2 is one of the UK's four major mobile networks, running its own 2G, 4G and 5G infrastructure and serving tens of millions of customers across the country. Its SIM only range covers everything from a basic 10GB rolling plan at £7 a month through to unlimited data contracts, and every single plan comes with O2 Priority which is a perks app that gets you early access to concert tickets, weekly Greggs treats, and discounts at restaurants and cinemas, included at no extra cost. If you are already a Virgin Media broadband customer, O2's Volt benefit automatically doubles your data allowance on eligible 12-month plans, which makes the pricing look even better.

That said, O2 is not the right answer for everyone, and the annual price rise policy is the biggest reason to pause. Every April, O2 increases your monthly bill by a flat £2.50 and unlike some networks that only apply this to new customers, this applies while you are still inside a fixed-term contract. On a 12-month deal signed today, your price will rise at least once before the contract expires. Which? survey ranked O2 14th out of 15 mobile networks in its January 2026 customer satisfaction survey with a score of 67%, and its Trustpilot score of 2.8/5 reflects widespread frustration with billing and customer service. Both of those are worth knowing before you commit.

This page lists every current O2 SIM only deal, explains what O2 Priority is actually worth, and compares O2 with competitors including giffgaff, EE and Three.

Quick Picks: Best O2 SIM Only Deals This Month

All O2 SIM Only Plans - November 2026

O2 currently offers SIM only plans on three contract lengths: 30-day rolling, 12-month fixed, and 24-month fixed. The 30-day and 12-month plans are listed on comparison sites with the most competitive pricing. The 24-month plans, including the unlimited Plus plan, are available directly on O2's website. All plans include unlimited UK calls and texts, 5G where available, eSIM compatibility, and O2 Priority.

12-Month Contracts

Prices below are fixed until April 2027, after which they rise by £2.50 every April.

30-Day Rolling Contracts

No long-term commitment. Cancel or switch plan with 30 days' notice. Prices on rolling plans are subject to the same April price rise.

24-Month Contracts (Direct from O2)

The Plus plan adds roaming in the USA, Canada, Mexico, Australia, New Zealand and Argentina on top of the standard 48-destination EU roaming.

What Is O2 Priority and Is It Worth It?

O2 Priority is a free app available exclusively to O2 and Virgin Media customers which you cannot access it if you are on giffgaff, Sky Mobile or Tesco Mobile, even though those networks use O2's infrastructure. In 2026, the main benefits include:

• Weekly treats: A £1 Greggs item each week, a hot drink or a savoury treat, up to four times a month. On rolling 30-day plans this is listed as a standard weekly benefit. Over the course of a year that is up to 48 items for £48, worth around £150 at Greggs' own prices, which effectively reduces the real cost of a £7/month plan if you use it consistently.
• Ticket pre-sales: O2 Priority members typically get access to concert and event tickets 48 hours before general sale, covering The O2 arena in London, O2 Academy venues across the UK, and selected other events including Secret Cinema. If you regularly attend gigs at O2 venues, this alone can justify the network choice because popular shows sell out in general sale, so early access has real monetary value.
• Cinema: Four Vue cinema tickets for £18, available once per month which is a saving of around £38 on standard Vue pricing for a group of four.
• Restaurant and going out discounts: Weekly Thirsty Thursday drinks offer at O'Neill's, Ember Inns and Sizzling Pubs. Fifty percent off chicken sandwich meals at Popeyes as a rolling offer.
• Streaming discounts: £2 off Disney+ Standard or Premium per month when added to your O2 bill, and £2 off Amazon Prime per month although the Prime discount does not apply if you already subscribe independently.
• Blue Mondays: Weekly prize draws with a headline prize (typically in the thousands of pounds) plus smaller prizes. Entry is free via the Priority app.

Priority offers rotate and change, so specific deals may not still be available by the time you read this. The core weekly Greggs treat and ticket pre-sale access have been consistent features throughout 2025 and 2026.

Is Priority worth it in practice? If you regularly go to gigs at O2 venues and you use the weekly Greggs treat, Priority adds genuine value that no other UK network matches at this price point. If you never attend concerts and do not use the treats, Priority is largely irrelevant to your decision and you should compare O2 on price and coverage alone where piggy back providers are often cheaper.

How does O2 compare with other networks?

O2 Volt: Double Data for Virgin Media Customers

If you have Virgin Media broadband at your address and you take out an eligible O2 Pay Monthly SIM on a 12-month plan, O2's Volt benefit automatically doubles your mobile data allowance within 14 days of both services being active at the same address.

This means the £8/month 50GB plan becomes a 100GB plan, the £10/month 80GB plan becomes 160GB, and the £15/month 250GB plan becomes Unlimited. For Virgin Media customers comparing SIM only deals, this makes O2's 12-month pricing considerably more competitive than the headline figures suggest. A 100GB 5G SIM at £8/month is difficult to beat on a 12-month contract from any network.

Eligibility: You need an eligible O2 Pay Monthly plan and Virgin Media broadband registered at the same address. Benefits apply automatically if you join both services after 18 October 2021. Customers who had both services before that date need to activate Volt manually in My O2 or My Virgin Media. If you change your O2 tariff, Volt benefits are temporarily removed and reapplied within 14 days.

O2 Coverage: How Good Is the Network?

O2 runs its own network infrastructure with 2G, 4G and 5G coverage. Its 4G network covers the majority of the UK population outdoors, and 5G is available in most major towns and cities. In areas where O2 and Vodafone have a network sharing agreement through their Cornerstone joint venture, indoor and rural coverage can be stronger than either network's standalone footprint.

In Which?'s January 2026 survey, customers gave broadly acceptable marks for day-to-day coverage, though some noted patchy performance in rural areas and on trains. EE is consistently rated as the most reliable network for 4G and 5G performance in independent testing, and Three scores lower than O2 in Which?'s overall survey. Before you sign up, you can check whether O2 covers your home, workplace and regular commute on O2's own coverage checker here.

O2 vs giffgaff: Which Is Better Value?

giffgaff runs entirely on O2's own network, the same masts, the same 4G, the same 5G. But O2 actually wins on price at most data tiers, particularly on rolling contracts, which is where giffgaff tends to charge significantly more.

On a 50GB rolling plan, O2 charges £8/month against giffgaff's £15/month, nearly double for the same coverage.

On fixed contracts the gap narrows, with giffgaff's 18-month plans more competitive, but O2's 12-month deals still match or undercut them at most tiers.

O2 wins on price at most rolling tiers and matches giffgaff on fixed contracts, while also including O2 Priority and Volt which are perks giffgaff simply does not offer. giffgaff's advantage is its no-credit-check 18-month plans, no mid-contract price rise, and better customer satisfaction scores. But on the headline question of value per GB, O2 is the stronger deal for most people, particularly for anyone who will use Priority or is already on Virgin Media.

How Does O2 Rate for Customer Service?

O2 scores below the market average across every major independent measure, and this is the clearest weakness in its offering.

Which?: O2 scored 67% in Which?'s January 2026 customer satisfaction survey of 5,173 people, ranking 14th out of 15 networks. The best-rated network in the same survey scored 83% which is a huge 16-percentage-point gap. Which? highlighted complaints about billing, customer service responsiveness, and the annual price rise policy.

Trustpilot: O2 scores 2.8/5 from 25,570 reviews, rated "Average." 80% of reviews are one star, making it one of the lowest-rated major networks on the platform. Common complaints include difficulty cancelling contracts, billing errors, and long waits to reach an agent.

How to contact O2:

• By phone (Pay Monthly): 202 from your O2 mobile (free), or 0344 809 0202 from any other phone. Availability is Mon to Fri 8am to 9pm, Sat 8am to 8pm, Sun 8am to 6pm
• By phone (Pay As You Go): 4445 from your O2 mobile (free), or 0344 809 0222 from any other phone
• Online chat: virtual assistant and chat via the O2 website or My O2 app
• In store: O2 operates retail stores across the UK
• Social media: @O2 on X, facebook.com/o2uk, @o2uk on Instagram
• Complaints: if O2 has not resolved your complaint within 6 weeks, you can escalate to CISAS (Communications & Internet Services Adjudication Scheme) free of charge

Who Should Get an O2 SIM Only Deal?

O2 SIM only is a good fit if:

• You are already a Virgin Media broadband customer who can benefit from the Volt double-data benefit makes O2's 12-month pricing hard to beat
• You regularly attend gigs or events at O2 venues and will benefit from Priority ticket pre-sales
• You want a major high street network with retail stores you can walk into
• You travel within Europe frequently and want 25GB of free roaming included on a standard plan
• You are on the 10GB plan and value the Priority Greggs treat, which substantially reduces the real monthly cost

O2 may not be a good fit if:

• Customer service quality is important to you as O2 ranks near the bottom of every independent measure
• You want guaranteed price certainty, O2's annual £2.50 rise applies even inside a fixed contract meaning the headline price may not be what you pay.
• You want the same coverage for less money and do not care about Priority as MVNOs like Tesco Mobile use O2's network and score far higher for customer satisfaction
• You need unlimited data at the lowest possible price as competitors like Three often have a cheaper deal.

How We Reviewed O2 SIM Only Deals

This review is based on O2's published SIM only plan pricing read from our comparison panel, where every O2 deal is sold by O2 itself, on 2 November 2026, giffgaff plan pricing read from the same panel on 2 November 2026, Which?'s January 2026 mobile network survey of 5,173 customers, and Trustpilot scores checked 15 October 2026. MoneyHQ does not carry out independent network testing or signal quality surveys.

Last reviewed: October 2026. Prices correct as of 2 November 2026.