Corporation Tax Act 2010 section 321

Supplement in respect of a post-commencement period

Section 321 allows qualifying oil and gas companies that incur ring fence losses to claim an additional tax relief known as post-commencement supplement, and explains how that supplement is treated for corporation tax purposes.

• A qualifying company that incurs a ring fence loss in any post-commencement period may claim post-commencement supplement for that period or any subsequent accounting period in which it carries on its ring fence trade.
• For periods beginning before 1 April 2017, the supplement is treated as a ring fence trade loss carried forward under section 45 against future ring fence trading income.
• For periods beginning on or after 1 April 2017, the supplement is treated as a ring fence trade loss carried forward under section 45B against future ring fence trading income.
• Claims for post-commencement supplement are subject to the same time limits as claims for group relief, as set out in paragraph 74 of Schedule 18 to Finance Act 1998.