Corporation Tax Act 2010 section 357UM

Northern Ireland supplementary deduction: amount

Section 357UM provides the formula for calculating the amount of the Northern Ireland supplementary deduction available to qualifying orchestra companies, and explains how the calculation is adjusted when an accounting period spans more than one financial year.

• The Northern Ireland supplementary deduction is calculated using the formula: (A − B) × (MR − NIR) / NIR, where A is the Northern Ireland additional deduction, B is any Northern Ireland losses surrendered, MR is the main corporation tax rate, and NIR is the Northern Ireland rate.
• The formula effectively uplifts the net additional deduction to compensate for the difference between the main corporation tax rate and the lower Northern Ireland rate.
• If the accounting period falls entirely within one financial year, the formula is applied directly using that year's rates.
• If the accounting period straddles two or more financial years, the deduction is calculated separately for each year, time-apportioned according to the proportion of the accounting period falling in each year, and then added together.