Losses on CT returns may be incorrect
If you receive a letter from HMRC about your corporation tax losses, don’t ignore it or you could end up overpaying. What’s going on?

An issue with corporation tax losses recorded on the CT600 form has been ongoing for some time. This may affect your company if you have reported losses in the following boxes:
- 805 and/or 810: UK property business losses;
- 830 and/or 835: non-trading losses on intangible fixed assets; and
- 850 and/or 855: management expenses.
It has been discovered that these boxes are sometimes showing different amounts than the tax computation. You may receive a letter saying that HMRC will use the computation figures. However, if you believe the CT600 is correct, you should contact HMRC on the email address included in the letter to explain why the CT600 figures should apply. Failing to do so could mean losses are underclaimed.
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