You can transfer an old ISA anytime and it will still be an old ISA. If you're getting 0.5%, it may be best to transfer sooner rather than later. Whatever you do with your old ISA, you can start one new cash ISA this year (if you are quick) and you can start another new cash ISA in the next financial year.

Hello, I have an ISA with Halifax of which on the 5/3/12 the interest went down to 0.5% and I received the gross interest. As I have already used my quota for the current tax year, is this the time to transfer to another provider, such as Santander? Or do I have to wait until the new tax year and then I can move it along and deposit the next years allowance? Is it possible to transfer to Santander now and then on the 6th of April deposit my new allowance? I have the next years ISA money waiting in a current account to go into another ISA, and would like to make the most of the current ISA money by moving it somewhere productive. Just unsure of when Im supposed to do this, now or wait till after the 6th? Hope someone can give me some clear advice! Thanks!