@ClaireS
This is best done when the minimum term of the contract has been met.
Your daughter will need to apply for her own contract as she'll need to pass credit checks and if successful, you can migrate her number to the new account.
I have no affiliation whatsoever with O2 or any subsidiary companies. Comments posted are entirely of my own opinion. This is not Customer Service so we are unable to help with account specific issues.
Please select the post that helped you best and mark as the solution. This helps other members in resolving their issues faster. Thank you.