Spouse Election form

just a quick question about the Spouse Election Form, which asks us to elect one or other of the couple to be the assessable spouse for the tax year, my questions are...

How do you choose is it the one with the most income that should be assessed are does it matter?
If I tick the box saying that I want all transferrable credits and cut off to be allocated to the assessable spouse will they just look at income for that year and whatever wasnt used give to the spouse that needs it?

They will transfer credits/cut off in accordance with your instructions ( or if the instructions are not clear, they will allocate as they see fit ) , the PAYE credit must remain with each spouse. As to who you designate, that is up to you, the assessable spouse does not necessarily have to be the one with most income.

thanks Graham