Hi
The guidance on HS343 advises ""If the result is a loss, you should ‘subtract’ this amount from the total gross interest you enter in box 3 on page Ai 1 of SA101 (
Additional information). (Round your loss ‘up’ to the nearest whole pound). You should not change the figures for net interest and tax deducted that you enter in boxes 1 and 2 on page Ai 1 of the additional information pages"". Box 3 cannot be lower than £0.00.
When tailoring your online return. On page 2 of 3, please tick 'yes' to the question ""Did you receive any other UK income, for example, employment lump sums, share schemes, life insurance gains?"". In section 4 - fill in your return, click on ""Enter other UK income details"" and tick 'yes' to ""Interest from gilt edge and other UK securities, deeply discounted securities and accrued income profits"".