What Is the Annual Investment Allowance?
The annual investment allowance (AIA) is a capital allowance that lets you deduct the full cost of qualifying plant and machinery from your taxable profits in the year you buy it. For the 2024/25 tax year, the AIA is set at £1 million [1][2]. That means if your agency spends up to £1 million on qualifying assets in a single accounting period, you can claim 100% tax relief immediately.
This is a significant relief for agency founders. Whether you are equipping a new office, upgrading your team's laptops, or investing in specialist software, the AIA can reduce your corporation tax bill pound for pound. For a limited company paying 25% corporation tax, a £50,000 equipment purchase could save you £12,500 in tax.
The AIA is available to businesses of any size, including sole traders, partnerships, and limited companies [3]. There is one exception: partnerships where one or more partners is a company cannot claim the AIA [3]. For most agency structures, this is not an issue.
How Much Is the AIA for 2024/25?
The AIA amount is £1 million [2]. This has been the permanent level since 1 January 2019, following several years of temporary increases and reductions [2]. The government confirmed in the Autumn Budget that the £1 million AIA will be retained [4].
If your accounting period is shorter than 12 months, the AIA is proportionally reduced. For example, if your accounting period is 9 months, the AIA will be 9/12 x £1,000,000 = £750,000 [2]. This matters if you start trading partway through the year or change your accounting period.
If two or more limited companies are controlled by the same person, they only get one AIA between them [2]. This is a common trap for agency groups. If you own multiple companies, you cannot claim £1 million per company. The £1 million cap applies across the group.
What Qualifies for the AIA?
The AIA covers most plant and machinery used in your agency's trade. This includes:
- Office furniture and desks
- Computers, laptops, and tablets
- Servers and networking equipment
- Fixtures such as lighting, heating, and air conditioning
- Kitchen and break-room equipment
- Specialist agency equipment like cameras, recording gear, or design hardware
You can only claim the AIA in the period you bought the item [2]. You cannot spread the claim over multiple years. If you buy an asset in March 2025, you must claim it in the 2024/25 accounting period that includes that date.
What Does NOT Qualify?
Several categories of expenditure are explicitly excluded from the AIA [3]:
- Cars, no AIA is available for cars, regardless of cost or emissions. You must use the main rate or special rate pool instead.
- Assets provided for the use of a person who is not a director or employee, if you buy a laptop for a contractor or freelancer, it does not qualify.
- Assets used partly for business and partly for non-business purposes, if you buy a camera you use 60% for agency work and 40% personally, the AIA does not apply. You must use the single asset pool instead.
- Assets used wholly or partly for a ring fence trade, this applies to oil and gas extraction, not agencies.
- Assets used wholly or partly for a trade of leasing or hiring, if your agency leases equipment to others, those assets do not qualify.
For most agency founders, the key exclusions are cars and assets used by non-employees. If you buy a company car, you cannot claim AIA. If you buy a laptop for a contractor, you cannot claim AIA.
How to Claim the AIA
Claiming the AIA is straightforward. You include the qualifying expenditure in your capital allowances computation as part of your tax return. For limited companies, this goes in the corporation tax return (CT600). For sole traders and partnerships, it goes in the self-assessment return (SA100).
You do not need to submit a separate form. Your accountant will calculate the AIA claim as part of your annual accounts preparation. If you use accounting software like Xero or QuickBooks, your accountant can tag qualifying purchases and run the capital allowances calculation.
If you are unsure whether an asset qualifies, ask your accountant before the year-end. Once the return is filed, you cannot go back and claim AIA for a previous period. The timing matters.
Real Example: A Digital Agency Buying Equipment
Let's say you run a 12-person digital agency in Manchester's Northern Quarter. Your accounting period runs from 1 April 2024 to 31 March 2025. During that period, you spend:
- £24,000 on 12 new laptops for your team
- £8,500 on office furniture and desks
- £3,200 on a new server and networking equipment
- £1,800 on a coffee machine and kitchen appliances
Total qualifying expenditure: £37,500. You can claim the full £37,500 as an AIA deduction in the 2024/25 accounting period. If your agency pays 25% corporation tax, that saves you £9,375 in tax.

