This is probably only resolvable once it has happened. A spouse / partner has an income of, say, £8,000 pension and £12,000 dividends in 2016/17. The spouse / partner applies for Marriage Allowance Transfer. Assuming that the other spouse / partner qualifies as a recipient of MAT - and that HMRC applies the legislation correctly - what happens? It could be that the recipient gets a £220 credit, but what of the applicant? More of the applicant's income will be taxed, but is that £1,100 at 7.5%?