What capital allowances can I claim?

Updated on 8 May 2019


On this page, we explain what capital allowances are and how to claim them. Remember that if you use the cash basis of accounting you will not claim capital allowances except on the purchase of cars.

What are capital allowances?

Expenses you incur in your business can either be revenue (trading) expenses or capital expenditure. Normally if an item will have a lasting benefit for the business, certainly longer than a year, it will be classed as capital expenditure. We explain how revenue expenses are dealt with on our What business expenses are allowable? page.

Capital allowances are a way of obtaining tax relief on some types of capital expenditure. They are treated as another business expense and so reduce your taxable profit within your basis period. You can find out more about accounting and basis periods on our How do I work out my taxable profits? page.


Matthew draws up his accounts for the year to 31 October 2018. Those accounts form his basis period for the 2018/19 tax year. Any capital expenditure in the year to 31 October 2018 is also eligible for capital allowances in the 2018/19 tax year.

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Does all capital expenditure qualify for capital allowances?

No. The expenditure must be on a particular type of asset. Generally you must own the asset on which the capital allowances are claimed. In other words if you have hired or leased the asset, capital allowances may not be claimed, but you may obtain tax relief on the rental costs as revenue expenditure.

There are special rules relating to assets acquired on hire purchase or finance leases. Generally, these assets are treated as belonging to the person using them, even though legal ownership may not pass until a final payment is made at the end of the contract term. In order to claim capital allowances, these assets must have been brought into use. Any interest on hire purchase items is a revenue (trading) expense and not part of the capital expenditure.

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How do I claim capital allowances?

They must be claimed in your Self Assessment tax return and they must normally be claimed by 12 months after the 31 January filing deadline for the return.

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How do I find out what types of expenditure qualify?

In these pages we are only going to look at plant and machinery allowances but you can find out about other types of allowances at GOV.UK.

The most common assets which you may purchase and that will qualify for capital allowances are as follows:

  • Motor car
  • Van
  • Computer, printer, etc
  • Tools, for example lawnmower, saw, etc
  • Specialist machinery

The main items that will NOT attract capital allowances include the cost of buildings or property, although it is possible that part of the cost of the building might relate to integral features or to fixtures. Note that you will only be able to claim capital allowances relating to a building if it is not a residential property and the property is used for business purposes, for example if is an office or a shop.

There are special allowances (called first year allowances) for energy efficient or environmentally beneficial plant and machinery.

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What are integral features?

Integral features are fittings within the building that cannot easily be removed, for example cold water systems, electrical systems, heating or ventilation systems, etc. See GOV.UK for more information.

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What are fixtures?

These are items that could be removed from a building without too much difficulty, for example shelving. See GOV.UK for more information.

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I use my car for private purposes as well as business purposes. Can I still claim capital allowances?

Yes, but you can only claim for the proportion of business use of the car.

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What rates are capital allowances given on plant and machinery?

The 'normal' allowance is a writing down allowance of 18%, or a special pool writing down allowance of 6%. But there is currently a much more beneficial allowance available, the annual investment allowance (see below).

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What is the annual investment allowance?

The annual investment allowance (AIA) provides 100% tax relief on assets qualifying as plant and machinery, subject to an annual maximum and excluding cars. Also, it is not possible to claim the AIA on assets which you owned and used for another reason (such as for personal use) before using them within the business, in which case you may use the small pools allowance or claim a writing down allowance in the main general pool.

The maximum amounts have varied since the AIA was introduced. The maximum amounts for the current and previous tax years are as follows:

Date max expenditure
From 1 January 2016 to 31 December 2018 £200,000
From 1 January 2019 to 31 December 2019 £1,000,000

There is more information on the AIA on GOV.UK.

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What happens if the capital allowances rates change part way through my accounting period?

You will need to apportion the rate at which the allowance is given.

If you have very high capital expenditure in an accounting period and the maximum AIA allowance changes part way through the accounting period then it is necessary to carry out a fairly complicated calculation which apportions the AIA limits to work out the maximum AIA allowance for the accounting period. For more information on this see GOV.UK.

If your expenditure is more than the AIA, then you can claim the AIA first and then claim writing down allowances on the balance.

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What is a writing down allowance?

It is a way of giving tax relief on part of the value of assets held in a pool. An example may make this clearer.

Cedric has a capital allowances pool brought forward of £24,000 before claiming allowances for 2018/19. If he has no additions or disposals of assets during that year, his claim for capital allowances would be as follows:

Written down value brought forward £24,000
Writing down allowance (18%) £4,320
Written down value carried forward £19,680

So Cedric can claim a writing down allowance of £4,320 and deduct that from his profits for tax purposes.

As most assets now qualify for annual investment allowance it is less common to see additions being made to the general writing down allowance pool. But sales of assets may impact on the pool.

What happens to capital allowances if accounts are drawn up for a period that is not 12 months?

Writing down allowances are pro-rated to the length of the period of accounts. So if a 15 month period of accounts is prepared (say, at the start of trading), writing down allowances are 15/12 of the usual amounts.

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What is the small pools allowance?

If you have a balance of £1,000 or less in your main general pool or special rate pool then you can claim capital allowances (called the small pools allowance) on the full amount. You cannot claim the small pools allowance and writing down allowances.

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What items fall into the special rate pool?

The main items in this pool will be long-life assets or cars with higher carbon dioxide (CO2) emissions.

These items only attract a writing down allowance at 6% each year but with the exception of cars you should be able to claim the annual investment allowance first before using the special rate pool.

There is more information on GOV.UK.

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What capital allowances will a car get?

The government continues to use capital allowances to try and encourage the use of more environmentally friendly cars. Broadly new cars with very low CO2 emissions will attract a full 100% allowance; cars with high CO2 emissions will be placed in the special rate pool and other cars will fall into the general pool. Any car that you use privately will be placed in a separate pool as allowances will be restricted by the amount of private use you have.

There is more information on GOV.UK.

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How do I find the actual levels of CO2 emissions of cars that decide what allowances I can claim?

You can look on the Vehicle Certification Agency website.

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What happens when I purchase an asset but cannot get AIA?

If you purchase an asset but the asset does not qualify for AIA, it will need to be added to the main capital allowances pool.

Look at the example above with Cedric again. Now assume that in 2018/19 he buys an asset that does not qualify for the annual investment allowance, so  the cost of the asset of £12,000 must be added to the general pool. His capital allowances computation for the general pool would be as follows:

Written down value brought forward £24,000
Add: purchased £12,000
Writing down allowance (18%) £6,480
Written down value carried forward £29,520

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What happens when I sell an asset?

If you sell an asset you deduct the sales proceeds from the balance of the pool, but you cannot deduct more than the original cost of the asset. In most cases AIA will previously have been claimed and as these assets would ordinarily have formed part of the writing down allowance pool, the proceeds must go through this main pool.

David has a general pool balance brought forward of £10,000. He sells a machine during the year for £1,200 (it had originally cost £3,500) and AIA had been claimed at the time in respect of this. His capital allowances computation for the general pool would be as follows:

Written down value brought forward £10,000
Less: proceeds from sale of machine £1,200
Writing down allowance (18%) £1,584
Written down value carried forward £7,216

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What happens if the sale proceeds are more than the balance of expenditure in the general pool

If you deduct the sale proceeds of the asset on which you have previously claimed AIA from the general pool and that makes the balance on the main pool negative, then instead of a capital allowance, a balancing charge has been generated and that is an amount that is added to trading profits rather than being deducted from them.


Brenda has a main pool balance brought forward of £1,500 at 6 April 2018. During the year 2018/19 she sells an item of equipment for £2,200. The equipment previously attracted a 100% allowance.

Written down value brought forward £1,500
Less: proceeds from sale of equipment £2,200
Balancing charge £700

So Brenda has £700 to add to her profits for 2018/19.

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Where can I find out more information about capital allowances?

This page gives you an outline of the rules on capital allowances but we cannot cover every scenario.

HMRC’s helpsheets HS222 and HS252 provide gives further information about capital allowances and there is further information on GOV.UK.

HMRC also produce webinars periodically which cover capital allowances and also have e-learning packages available. For more information on these learning tools, see GOV.UK.

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