Writing down allowances 

When you buy business assets (external link) you can usually deduct the full value from your profits before tax using annual investment allowance (external link) (AIA). 

Use writing down allowances instead if: 

• you have already claimed AIA on items worth a total of more than the AIA amount (external link) 
• the item does not qualify for AIA (for example, cars, gifts or things you owned before you used them in your business) 

Writing down allowances is when you deduct a percentage of the value of an item from your profits each year. 

The percentage you deduct depends on the item. For business cars (external link) the rate depends on their CO2 emissions. 

Work out the value of your item 

In most cases, the value is what you paid for the item. Use the market value (the amount you would expect to sell it for) instead if: 

• you owned it before you started using it in your business 
• it was a gift 

How to claim 

Group the things you have bought into pools (external link) based on the percentage rate they qualify for. 

When you know the rate for your items, work out how much you can claim (external link) and deduct it from your profits before tax on your tax return (external link). 

The amount left in each pool becomes the starting balance for the next accounting period.