My situation - what should i do?

ozzage

You also need to weigh up the advantages of salary sacrifice into your OWN pension even once below the 40% rate (i.e. a very inviting 12% NIC saving on top of the 20% tax relief), with the fact that your wife is probably going to have a partly unused personal allowance on retirement due to her lack of pension provision.

Therefore even though you'll save an extra 12% now if you pay into your own pension, you'll potentially save 20% tax later when you draw it out if you pay into your wife's instead.

Basically, as well as considering the savings now you also need to do the maths on this well to ensure that you both use your personal allowances as effectively as possible to reduce your tax later.