Capital allowances in the CT600

Entering assets

1. Add each addition

   Under "Additions" enter the description, date, cost, type (main rate plant, special rate, or a car by emissions), whether it is new, and the claim.

2. Choose the claim

   "Best claim" picks the claim for you. You can choose the annual investment allowance, full expensing, the 50% or 40% first-year allowance, the 100% zero-emission car allowance or the pool only.

3. Add disposals

   Enter the proceeds, original cost and pool for anything sold.

4. Recalculate

   Press "Save and recalculate".

Rates used

• Annual investment allowance of £1,000,000 a year, reduced for short periods and shared across a group.
• Full expensing at 100% on new main rate plant, and 50% on new special rate plant.
• 40% first-year allowance on new main rate plant bought from 1 January 2026.
• Main pool writing-down allowance 18%, then 14% for periods from 1 April 2026, with a blended rate for a period that spans that date. Special rate pool 6%.
• Pools of £1,000 or less are written off.

Sources

The rates are in capital allowances rates for 2026, with links to GOV.UK.

Short-life and long-life asset pools, research and development allowances and land remediation are entered outside Accountin.