Expenditure within the AIA qualifies for 100% allowance in the year of purchase. AIA was capped at £200,000 per annum up to 31 December 2018. This limit was temporarily increased to £1m per annum for each of the two years ended 31 December 2020, before reverting back to £200,000 on 1 January 2021. This increase in the AIA cap will help businesses invest in equipment and fixtures (cars and buildings don't qualify), with 100% tax relief in the year of purchase. However, great care is needed to calculate the available AIA for accounting periods which straddle the various changes.