New Customer

[Newcustomerrrr]

Hi, I want to begin a new contract with O2 but I also want to choose the date the switch goes through.

[Bambino]

@Newcustomerrrr This is not O2. This is a customer community. You need to speak to customer service. 

How to find help & contact O2: A Guide - O2 Community

[QP999]

I suspect as the customer you can start the contract when you want, o2 will guide you through when they need the order to happen to fit in with your timescales.  O2 doesn't seem to make it easy and then refers you to this area who then tell you to go back. to o2.

On the upside thou when they get it right the service they have over others are amazing ( EU roaming etc )

[MI5]

@Newcustomerrrr 

If you're talking about the switch to your current number, you can control that by choosing the time to submit your PAC to port in.

Guide: Migration & porting into O2 

If you mean when to control your billing date, this will be approx 2 days after you join for the regular billing date to be set and is due to be paid 14 days after, so you can use that as a guide to know when to have the money available to pay.

https://www.o2.co.uk/help/account-and-billing