Our Best SIM Only Deals

Save money with a sim only plan

Phones Tablets Mobile broadband

Find your perfect Pay Monthly SIM

Happy with your phone? Save with a Pay Monthly SIM only deal. Keep your number when switching networks and choose from flexible 30-day, 12-month, or 24-month plans. Browse our best SIM only contracts today.

Roam freely

We're the only major network that is not reintroducing EU roaming charges. Up to 25GB.

Contract length
Featured

Sort by
O2 recommends

Filter by
0 filters applied

Unlimited

24 Month

Unlimited UK Minutes & Texts

Offers included

Get Unlimited data for £26, for 24 months. Ends 4 June.

Get boosted broadband speeds and more when you’re with both Virgin Media and O2.

Roam freely in the EU. Only on O2. Up to 25GB.

See all offers

Total monthly cost increasing to:

£27.80 from
Apr 2026 bill

£29.60 from
Apr 2027 bill

Airtime Plan will increase every year thereafter by £1.80 from April bill, except Data Only and Smartwatch Plans which will increase by 75p

100GB

24 Month

Unlimited UK Minutes & Texts

Offers included

Get 100GB for £21, for 24 months. Ends 4 June.

Get double data (200GB), boosted broadband speeds and more, when you’re with both Virgin Media and O2.

Roam freely in the EU. Only on O2. Up to 25GB.

See all offers

Total monthly cost increasing to:

£22.80 from
Apr 2026 bill

£24.60 from
Apr 2027 bill

Airtime Plan will increase every year thereafter by £1.80 from April bill, except Data Only and Smartwatch Plans which will increase by 75p

Unlimited Plus

24 Month

Unlimited UK Minutes & Texts

Offers included

Get Unlimited data for £27.99, for 24 months. Ends 4 June.

Get boosted broadband speeds and more when you’re with both Virgin Media and O2.

Roam at no extra cost in 75 destinations worldwide, including the EU, the USA, Australia and Mexico.

See all offers

Total monthly cost increasing to:

£29.79 from
Apr 2026 bill

£31.59 from
Apr 2027 bill

Airtime Plan will increase every year thereafter by £1.80 from April bill, except Data Only and Smartwatch Plans which will increase by 75p

Unlimited Ultimate

24 Month

Unlimited UK Minutes & Texts

Offers included

Get Unlimited data for £36.49, for 24 months. Ends 4 June.

Get boosted broadband speeds and more when you’re with both Virgin Media and O2.

Roam freely at no extra cost with O2 Travel Inclusive Zone Ultimate. 123 destinations worldwide.

See all offers

Total monthly cost increasing to:

£38.29 from
Apr 2026 bill

£40.09 from
Apr 2027 bill

Airtime Plan will increase every year thereafter by £1.80 from April bill, except Data Only and Smartwatch Plans which will increase by 75p

View all results

FAQs

A Pay Monthly SIM Only deal gives you a SIM card with a fixed monthly allowance of minutes, texts, and data, without a new phone. It’s perfect if you already have a device and just need a SIM plan to stay connected.

With an O2 SIM Only deal, enjoy a flexible plan with generous data, texts and minutes, predictable billing, and access to our reliable 4G and 5G network.

Plus, get exclusive perks with O2 Priority and earn extras with O2 Rewards.

Yes, keeping your current phone number is easy. Just request a PAC code from your existing provider, give it to us, and we’ll transfer your number to your new O2 SIM Only contract.

At O2, we have a range of SIM Only plans to suit every need. You can even adjust your contract length and tailor your airtime to suit you.

Want more airtime? We've got you covered. Our Plus Plan and Ultimate plans allow you to level up your Airtime Plan with a heap of extras. You can even benefit from O2 Switch Up and swap your phone for a new one every 90 days. And, get an extended 3-year warranty and roam freely up to 25GB while travelling abroad.

At O2, we understand that everyone has different data needs. That's why our plans are customisable.

The amount of data you need is entirely up to your usage habits. If you regularly connect to WiFi or hotspots, you might not need as much data. But on the flip side, if you live somewhere with a poor WiFi connection or are regularly on the go, opting for more data might be the best decision.

Yes, you can. Stream, download and scroll without restrictions with one of our unlimited data SIMs.

Yes, they do. You can roam freely in the EU, up to 25GB.

With a Plus Plan or Ultimate Plan, you can utilise your airtime across even more destinations including the USA, Mexico, Canada, New Zealand, Argentina and Australia. Learn more about EU Roaming.

Yes, you can. As long as your phone is 5G compatible, you can enjoy super-fast 5G speeds with a Pay Monthly SIM from O2.

The minimum contract length is 30 days. You can also choose a 12-month, or 24-month contract, whatever works for you.

There are four types of SIMs available: standard, micro, nano and eSIM. An eSIM lets you manage your Airtime Plan without the use of a physical SIM.

If you're unsure what size you need, it's best to check the instructions that came with your device.

Monthly price of your Airtime Plan will increase by £1.80 each April, except Data Only and Smartwatch Plans which will increase by 75p. Out of bundle charges increase by 5% every 1 April.