Non bundle sim plans?

[DameHannahRelf]

Can anyone recommend a sim card that isn't a bundle?

It's for a relative who rarely uses their mobile to make calls, but would like to be able to top up £10 credit for the odd text and emergencies, and not have it run out at the end of the month. If possible they would like to keep their number, but happy to change if they have to.

You could try giffgaff.

You can top up or you can pay a small amount each month it’s upto the user. You can transfer the number just require a pac code from current network.