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Tax, Accountancy and VAT


Capital Allowances

The rules for Capital Allowances (CAs), like most tax issues, are complex, and should be checked carefully when planning business expenditure and completing tax returns. Here we briefly identify the main rules which will affect the small business. Please email us if you have further questions.

There is no obligation to claim CAs in any particular year. If no claim is made, the value for CAs is simply carried forward unchanged. Alternatively, a part claim can be made. This may be useful if a small profit is made, and the trader's personal allowance would be wasted if CAs were claimed.


Profits before CAs£13,000
CAs available(£3,000)
Taxable profit after CAs£10,000

This is less than the Personal Allowance (PA), which is £11,500 in 2017-18. It is therefore better to claim only £1,500, and claim further CAs in future years.
Tax Planning Point
Capital Allowances are flexible, and can be used in full or in part, or not at all, in any particular year. If profits are low, it may be worth ignoring CAs in order to preserve the Personal Allowance.

Annual Investment Allowance (AIA)

An AIA of £200,000 is currently available for most Plant and Machinery (P&M) except cars, which means that the full cost of new equipment can be offset against tax. The allowance is reduced pro-rata for periods of less than 12 months.
Tax Planning Point
Equipment bought on the last day of the trading period will qualify for 100% AIA in that year; if the purchase is delayed for one day, the AIA will not be available until one year later.

The Main Pool

Most expenditure on which the AIA is not claimed goes into the Main Pool. An amount of 8 or 18% of this Pool can be claimed each year, depending on the type of equipment, with the residue being carried forward to the following year. The value of the Pool at any time is known as the "written down value" (WDV). The amount deducted from the Pool and claimed for tax in a year is the "writing down allowance" (WDA).


Pool written down value b/fwd:£5,000
Additions during year£2,000
Disposals during year (sale price)(£1,000)
WDA @18%(£1,080)
WDV c/fwd£4,920

Pools of value £1,000 or less can be written off in full. It is therefore desirable to reduce the Pool value to this value. However, the effect of the 18% WDA is that the Pool value decreases only slowly. Where possible therefore, it is desirable to keep new assets out of the Pool.

One way of doing this is to classify new assets as "short life".

Short Life Assets

It has for a long time been possible to treat some assets as "short life assets". Typically, this would have been used for items such as computers, which are likely to be written off within a relatively short period. Instead of the asset joining the main Pool, and being merged with assets which are written down slowly, the asset is treated separately as a Short Life Asset, and a balancing allowance is claimed when the asset is sold. (A balancing allowance is a CA for the unclaimed value of an asset. It will not arise on assets within the Pool, which are merged with other assets.)


A computer value £2,000 is purchased in 2015-16 and sold in 2017-18 for £200.

WDA 18%£360
WDV c/fwd£1,640

WDA 18% £295
WDV c/fwd £1,345

Disposal proceeds£200
Balancing allowance claimed£1,145

The effect is to accelerate the CA claim. It means that the business has obtained tax relief for the full cost of owning the asset (£2,000 - £200), by claiming £360 + £295 + £1,145.

If the computer had entered the Main Pool, the WDA in 2017-18 would have been only £242 (18% of £1,345), and an ever diminishing claim would have continued in future years. (Of course, in many cases the AIA would be used to claim the full amount in 2015-16; however, short life treatment would be useful if the AIA had not been claimed, for instance if profits that year had been low).
Tax Planning Point
If the AIA is not used, it may be worth making a Short Life Asset election to accelerate CAs.
A final point on short life assets; the rules do not insist that only assets of a short expected life, such as computers, are so classified. If the asset has not been sold within 8 years (4 years prior to April 2011), it reverts to the Main Pool.

Private Use Assets

Certain assets do not join the Main Pool. These are assets which have private use, on which separate calculations are made, so that the trader is charged for the private use. Suppose a computer value £1,000 is purchased, which is used 20% privately. The AIA or WDA is calculated, but is then reduced by the extent of the private use.


Cars are treated for CAs according to their CO2 emissions.
Private use does not apply to companies which buy cars. Instead, there is a benefit in kind charge on the employee.
Tax Planning Point
New cars, with CO2 emissions of no more than 95 g/km, receive an FYA of 100%. In other words, such a car is fully deductible for tax in the year of purchase, subject to any private use deduction.
The HMRC leaflet HS 252 Capital Allowances and Balancing Charge explain the rules further, with examples.

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