One has to second the sound advice provided by FL245. In the couple of occasions over many years when one has tried to be honest with the taxman, the result has been nothing but trouble leading to the need for an accountant anyway. This has incurred unnecessary expense as he invariably had to sort out the misconceptions and false assumptions to which the jolly old revenue had jumped. Remember too, that the taxman is a far more belligerent beast now than he used to be. The sums of money involved are not really the issue here. It's more one of clearing up the matter as expeditiously as possible. A quick letter from any decent accountant would probably sort things out. The tax man would, on the whole, far rather deal with a professional than the enthusiastic amateur. It rather depends on whose desk at HMRC your file ends up. You should perhaps always assume that the taxman is a thoroughgoing nasty little bastard until he proves that he is really a very decent sort, which of course, he is!