United Kingdom corporation tax loss relief rules are complex. United Kingdom corporation tax charges income and gains that fall within certain headings, all of which are defined by statute. Different loss relief rules apply to each separate heading.
Case I of Schedule D
This Case covers trading profits arising from a UK trade. Case I losses are calculated in the same way as trading profits<sup>1</sup>.
A company<sup>2</sup> that is part of a group or a consortium may group relieve its Case I losses in excess of the other taxable profits arising in the company in that period, provided there is a group or consortium company with sufficient taxable profits to accept that group relief.
A company may elect to set the Case I losses arising in an accounting period against other taxable profits arising in the period<sup>3</sup>. If there are still unutilised Case I losses that arose in that period, a company may elect to carry these back against its taxable profits of the last 12 months<sup>3</sup>. Where a trade ceases, the company may elect to carry back its Case I losses arising in the last 12 months of the trade against its taxable profits arising in the preceding 36 months<sup>4</sup>.
Any Case I losses unutilised in a period are automatically carried forward to be utilised against the next Case I profits arising from the same trade<sup>4</sup>.