Switch to SIM Only and Keep Your Number

When you get a phone on contract, your monthly bill pays for two things: the handset and your calls, texts and data. Once the phone is paid off, you own it. But depending on your provider, you might keep paying a price that still includes it, which is a bit like paying off a car and then carrying on with the instalments.

Switching to a SIM-only plan when your contract ends is one of the easiest savings going. You keep your phone, you keep your number, and you only pay for the airtime. Here's how to do it properly.

step 1: find out when your contract ends

Text INFO to 85075. It's free, and your provider will text back with your contract end date, any charges for leaving early, and how to get your switching codes. Your provider also has to tell you when your contract is about to end, so keep an eye out for that message.

If you leave before the end date you may have to pay early termination charges, so it usually pays to wait until you're out of contract or very close to it.

step 2: check your phone is unlocked

A locked phone only works with the network that sold it. Since December 2021, UK networks haven't been allowed to sell locked phones, so if you got yours after that it should be fine. If your phone is older, ask your current provider to unlock it before you switch. Most do it free these days.

If you're not sure, borrow a friend's SIM from a different network and pop it in. If it works, you're unlocked.

step 3: work out how much data you really use

This is where most people overpay. Your phone keeps count for you:

iPhone: Settings, then Mobile Data, then scroll down to see usage for the current period.
Android: Settings, then Network or Connections, then Data usage.

Look at a full month if you can. If you're on wifi at home and at work, the answer is often much lower than you'd guess. Our SIM-only comparison has a rough guide to light, medium and heavy use, and lets you filter by data so you're not paying for gigabytes you'll never touch.

step 4: pick a network that works where you are

Coverage matters more than brand. The UK's masts are owned by a handful of network groups, and lots of cheaper brands (called MVNOs) run on those same masts. That means a lower-cost SIM can give you the same signal as the big name it runs on.

Check the coverage map for wherever you spend your time: home, work, the commute, your parents' house. Then compare SIM-only deals on the network that wins for you.

While you're at it, think about rolling vs fixed. A 30-day rolling SIM lets you leave whenever you like and sidesteps mid-contract price rises. A 12-month plan can be a little cheaper each month but ties you in. There's rarely a good reason to sign up for longer than 12 months on a SIM alone.

step 5: get your code and switch

To keep your number:

text PAC to 65075. You'll get a PAC code back straight away, valid for 30 days.
order your new SIM (or eSIM, if your phone supports it) and give the new provider your PAC code.
your number moves across, usually within one working day. You might lose signal for a short while on switch day.

Want a fresh number instead? Text STAC to 75075.

You don't need to ring your old provider to cancel. Once the switch goes through, your old contract ends, and they can't charge you for a notice period after the switch date.

step 6: check two more things before you go

roaming. If you travel, check what the new plan charges abroad. Some SIM-only deals include roaming in Europe and some don't. For trips further afield, a travel eSIM is often far cheaper than roaming on your main plan.
anything bundled in. If your old contract came with a streaming subscription or other extra, it'll usually end when the contract does. Decide whether you actually want to pay for it separately. Our streaming comparison can help there.

the short version

text INFO to 85075 to find your end date
make sure your phone is unlocked
check how much data you really use
pick a network that covers your life, then compare SIM-only deals
text PAC to 65075 and hand the code to your new provider

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