If you have bought equipment for your agency this year, you might be able to claim 100% tax relief on the cost through the Annual Investment Allowance (AIA). The AIA capital allowance is one of the most straightforward tax reliefs available to agency founders, yet many leave money on the table by not claiming it properly.
Here is what qualifies, what does not, and how to make the claim.
What Is the AIA Capital Allowance?
The Annual Investment Allowance lets you deduct the full cost of qualifying plant and machinery from your taxable profits in the year you buy it. For most agency businesses, that means you get 100% tax relief immediately rather than spreading the cost over several years through writing down allowances [1].
The current AIA amount is £1 million [2]. That applies to both sole traders and limited companies [2]. For the vast majority of agencies, that limit is more than enough to cover a year's worth of equipment purchases.
If your accounting period is shorter than 12 months, the allowance is pro-rated. A 9-month period gives you 9/12 of £1 million, which is £750,000 [2].
What Agency Equipment Qualifies for AIA?
Qualifying expenditure covers most tangible assets your agency uses to operate. The key test is whether the item counts as "plant and machinery" for tax purposes.
Typical qualifying items for an agency include:
- Computers, laptops, and monitors
- Servers and networking equipment
- Office furniture (desks, chairs, shelving)
- Fixtures and fittings (lighting, air conditioning, security systems)
- Phone systems and headsets
- Cameras, video equipment, and production gear for creative agencies
- Certain types of software (where it is integral to the functioning of equipment)
You can claim AIA on equipment purchased through a hire purchase agreement or a loan, but not through a leasing agreement [3]. The key point is that the business must own the asset, or be contractually committed to owning it at the end of the agreement.
What Does Not Qualify?
Some common agency expenses do not qualify for the AIA capital allowance. These include:
- Buildings and land (though certain integral features within a building may qualify)
- Cars (cars have their own capital allowance rules)
- Assets used partly for non-business purposes (you must apportion the claim)
- Items bought in the final accounting period before your business closes [2]
- Assets you already owned before starting the business
If you are a sole trader or partnership using the cash basis of accounting, you can only claim capital allowances on business cars [1]. That is a common trap for agency founders who start as sole traders and buy equipment before switching to limited company status.
How to Claim the AIA Capital Allowance
You claim the AIA in your tax return. For a limited company, that means including the claim in your Company Tax Return (CT600). For a sole trader or partnership, it goes on your Self Assessment tax return (SA100).
You can only claim AIA in the period you bought the item [2]. You cannot hold the claim back for a later year. If you miss the claim, you lose the benefit of the 100% allowance for that asset, though you can still claim writing down allowances at a lower rate in future years [1].
You do not need to have paid for the item yet. The claim is based on when you became entitled to the asset, not when the invoice is settled [3]. That is useful if you are buying equipment on credit terms.
Full Expensing and the 50% First-Year Allowance
Since 1 April 2023, companies can also claim full expensing on qualifying plant and machinery investments [1]. This is a separate relief from the AIA, but it achieves the same result: 100% tax relief in the year of purchase.
Full expensing applies to main pool assets (typically the same items that qualify for AIA). There is also a 50% first-year allowance for special rate assets, such as integral features in buildings and long-life assets [1].
For most agency founders, the AIA capital allowance remains the simplest route. Full expensing is worth knowing about if your equipment purchases exceed £1 million in a year, but that is rare for agencies.
From 1 January 2026, a 40% first-year allowance will be available for qualifying plant and machinery purchased after that date [1]. That is worth noting if you are planning significant capital expenditure in 2026 and beyond.
Connected Companies and the AIA Limit
If you control two or more limited companies, they only get one AIA between them [2]. That matters if you run multiple agencies under separate companies. You cannot double up on the £1 million allowance by splitting purchases across your group.
The same rule applies to partnerships. Each partner can claim AIA on their share of the partnership's qualifying expenditure, but the overall limit for the partnership is the same as for a company [4].
If you are considering a holding company structure for your agency group, speak to your accountant before making large equipment purchases. The AIA rules for connected companies can catch you out if you are not careful.
Practical Example: A Digital Agency Buying Equipment
Let us say you run a 12-person digital agency billing £800k per year. In March 2025, you spend £34,200 on new MacBooks, monitors, desks, and a server upgrade. All of these items qualify as plant and machinery.
Without the AIA, you would claim writing down allowances at 18% per year on the reducing balance. That gives you roughly £6,156 relief in year one, then smaller amounts in subsequent years.
With the AIA capital allowance, you claim the full £34,200 in the year of purchase. If your corporation tax rate is 19%, that saves you £6,498 in tax. If you are in the 25% main rate band, the saving is £8,550.
The difference is significant, and it is entirely legitimate. You just need to make sure the claim is included in the right period.
Common Mistakes Agency Founders Make
Missing the claim entirely is the most common error. Many agency founders treat equipment purchases as general expenses rather than capital items. If you put a £2,000 laptop through the profit and loss as a revenue expense, you get the tax relief, but you also distort your accounts. Capitalising the asset and claiming AIA is the correct treatment.
Another mistake is claiming AIA on assets that do not qualify. Software licensing, for example, is usually a revenue expense, not a capital item. But if you buy a perpetual software licence that is integral to your server hardware, it may qualify. The distinction matters.
Finally, some agency founders forget to claim AIA in the year of purchase and try to claim it retrospectively. That does not work. You must claim in the correct period [2].
Should You Change Your Year-End to Maximise AIA?
If you buy a significant capital item just after your year end, you could consider changing your accounting date to bring the purchase into the earlier period [3]. That is a legitimate planning technique, but it has wider implications for your filing deadlines and tax payments.
Talk to your accountant before making that decision. Our ICAEW qualified team at Agency Founder Finance can walk you through the trade-offs. We work exclusively with agency founders, so we understand the specific equipment you are buying and how to structure the claim.
If you want to review your current capital allowance position, get in touch. We can check whether you have missed any claims in previous years and help you plan future purchases for maximum tax efficiency.
For more on how we help agency founders with their tax and compliance, see our full range of services. We cover everything from salary and dividend planning to IR35 compliance.