If you don't know your home phone number, simply dial your mobile (or a friend or family member's) from the landline. You should also dial 1470 before the mobile number if you have number withhold.
Make sure you don’t answer or let the voicemail kick in, otherwise you'll be charged for the call. Just allow it to ring a couple of times to register and make a note of the number.
Don't have access to a mobile?
The account holder can call us on 0800 800 150, but you must be able to tell us your account number and be ringing from that landline.
Where do I find my BT account number? >
Line not connected?
If your line isn't actually connected, check how to order a new BT phone line here >
Alternatively, you can call us on 0800 800 150.