Our Best SIM Only Deals

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Find your perfect Pay Monthly SIM

Happy with your phone? Save money with a Pay Monthly SIM. You can even keep your number if you've joined from another network. Browse our best SIM only deals today, and choose a 30 day, 12 month or 24 month contract.

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

24 Month

Unlimited UK Minutes & Texts

100GB

24 Month

Unlimited UK Minutes & Texts

20GB

24 Month

Unlimited UK Minutes & Texts

6GB

24 Month

Unlimited UK Minutes & Texts

250GB

24 Month

Unlimited UK Minutes & Texts

30GB Ultimate

24 Month

Unlimited UK Minutes & Texts

150GB Ultimate

24 Month

Unlimited UK Minutes & Texts

3GB

24 Month

Unlimited UK Minutes & Texts

12GB Plus

24 Month

Unlimited UK Minutes & Texts

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FAQs

It’s a SIM that comes with a Pay Monthly plan. You’ll pay a fixed amount each month for a set allowance of minutes, texts and data. It's like a traditional phone deal, but you don't get a new device, you just get the SIM.

With an O2 Pay Monthly SIM deal, you get to enjoy a host of benefits tailored to your needs.

Stay in control of your tariff with the predictability of a monthly bill, making budgeting a breeze. Our flexible pay monthly plans offer generous allowances of minutes, texts and data, so you can stay connected without worrying about running out.

You’ll have access to our extensive network coverage, providing reliable 4G and 5G services across the UK. And with O2 Priority, you can unlock exclusive discounts and perks, from early access to gigs to once-in-a-lifetime prizes.

Plus, with O2 Rewards, you earn rewards just for being with us, making your Pay Monthly SIM deal even more awesome.

Absolutely. Simply request a PAC (Porting Authorisation Code) from your existing provider, share it with us, and we'll make sure your number is transferred over without a hitch.

We have a varied range of pay monthly SIM Only plans to choose from. 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 allows you to level up your Airtime Plan with a heap of extras. Benefit from O2 Switch Up and swap your phone for a new one every 90 days. 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, 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 each April from April 2025 by the Retail Price Index rate of inflation announced in February each year plus 3.9%. If RPI is negative, we'll only apply the 3.9%. See o2.co.uk/prices.