Temporary increase to £1,000,000. The AIA was introduced in April 2008 as a tax incentive for businesses to invest in new equipment, machinery etc. It allows businesses, regardless of size, to deduct the full cost of plant and machinery (excluding cars) from their profits in the year of purchase, rather than being spread over ten years or more. Since 1 January 2016 the annual limit has been £200,000 but between 1 January 2019 and 31st December 2020 there is a temporary increase to £1,000,000 to incentivise investing in business assets to further enhance your business.