I had asked my client's wife to register for the new marriage allowance so she could transfer 10% of her SPA to her husband. I have to say the subsequent transfer was amazingly quick resulting in a new code for him for 2016/17 and the processing of his 2015/16 SA return followed by a calculation incorporating the £212 transfer, very impressed with the speed of all this. However, at the same time HMRC have issued a P800T for his wife showing a refund of about £260 and the refund having been made at the same time. This P800T was not requested by either his wife or myself as her agent. The estimated taxed interest is clearly incorrect as all her interest is either within an ISA or is paid gross as she is a non-taxpayer and has been for some years now. The estimate by HMRC must be 5 or more years old at least, very worrying. She now has a refund which I am sure was not due, the refund was made at the same time the P800T was issued which gave no one any time to query the P800T and now she will have the hassle of having to inform HMRC after gathering all her interest figures for 2015/16 to have that corrected and of course to have to return the refund. I think two issues arise here, HMRC using estimates for data captured years ago and making an immediate refund on a calculation they know contains what it highly likely to have out-dated information.