# Capital allowances calculator for companies

Source: https://www.statutoryaccounts.io/tools/capital-allowances-calculator/

Last reviewed: 28 October 2026

Enter a company's plant and machinery spending and its pool balances to see the capital allowances for one accounting period: the £1 million annual investment allowance, full expensing, the 50% and 40% first-year allowances, and writing-down allowances. The main pool rate falls from 18% to 14% for periods from 1 April 2026, with a hybrid rate across that date.

## Key facts

| | |
| --- | --- |
| Annual investment allowance | £1,000,000 a year, in proportion for a shorter period; one AIA shared by companies under common control |
| Full expensing | 100% on new and unused main-rate plant and machinery bought on or after 1 April 2023, companies only, no end date; not cars, not for leasing |
| 50% first-year allowance | New and unused special rate plant and machinery, companies only; the rest goes to the special rate pool |
| 40% first-year allowance | New main-rate plant and machinery bought on or after 1 January 2026; leasing allowed; the rest goes to the main pool |
| Main pool writing-down allowance | 18% before 1 April 2026; 14% for periods beginning on or after it; a hybrid rate for a period across the date |
| Special rate pool | 6% a year |
| Small pools allowance | Write off a pool of £1,000 or less |
| Zero-emission cars and charge-points | 100% first-year allowance to 31 March 2027 for companies |

As at 25 October 2026.

## Work out the allowances

Enter the period and the expenditure and select Work out the allowances.

## The main pool rate across 1 April 2026

For a chargeable period that straddles 1 April 2026, the main pool rate is a hybrid: (18 × days before 1 April 2026 + 14 × days on or after it) ÷ days in the period, rounded up to two decimal places (Finance Act 2026, section 28). Three examples:

| Accounting period | Days before / from 1 April 2026 | Main pool rate |
| --- | --- | --- |
| 1 January 2026 to 31 December 2026 | 90 / 275 | 14.99% |
| 1 July 2025 to 30 June 2026 | 274 / 91 | 17.01% |
| 1 October 2025 to 30 September 2026 | 182 / 183 | 16.00% |

## Worked example

A company with a year from 1 April 2026 to 31 March 2027 has a main pool of £50,000 brought forward. In the year it buys new machinery for £100,000, spends £20,000 on integral features and buys a car with emissions under 50 g/km for £15,000.

| Item | Allowance |
| --- | --- |
| Annual investment allowance on the integral features | £20,000 |
| Full expensing on the new machinery | £100,000 |
| Writing-down allowance: (£50,000 + £15,000) × 14% | £9,100 |
| Total allowances | £129,100 |
| Main pool carried forward | £55,900 |

The calculator uses the annual investment allowance first on special rate expenditure, which would otherwise get 50% or 6%, then on main-rate expenditure that cannot be fully expensed. A company may allocate it differently in its return.

## Where the allowances go on the CT600

| Allowance | CT600 box (trading) |
| --- | --- |
| Annual investment allowance | 690 |
| Full expensing: allowance / balancing charge | 688 / 689 |
| 50% special rate allowance / charge | 693 / 694 |
| Special rate pool: allowance / charge | 695 / 700 |
| Main pool: allowance / charge | 705 / 710 |
| 40% first-year allowance | 725 for now; qualifying expenditure in 760 |

HMRC has said that until its service update in April 2027 the 40% allowance goes in box 725 (750 for non-trading), and that for periods beginning on or after 1 April 2026 zero-emission cars and charge-points also go in 725 or 750.

## Assumptions and limits

- One accounting period, at most 12 months. For a shorter period the annual investment allowance and the small pools allowance are reduced in proportion (9 months gives £750,000); the calculator uses whole months where the period is whole months and days over 365 otherwise. It does not work out writing-down allowances for a period shorter than 12 months.
- Not for the final period of trade. In the period a trade ceases there is no annual investment allowance or full expensing, and the pools give balancing allowances or charges.
- Disposals. Proceeds from main and special rate pool assets reduce the pool; more than the pool is a balancing charge. For an asset on which full expensing was claimed, the whole proceeds are a balancing charge outside the pool, as the calculator assumes 100% was claimed. Disposals of assets that had the 50% allowance are not covered.
- Cars never get the annual investment allowance, full expensing or the 40% allowance. Structures and buildings allowance (3% a year) and short-life assets are not covered.
- Rates as at 25 October 2026, before the Autumn Budget on 28 October 2026.

## Frequently asked questions

**What is the writing-down allowance from April 2026?**
For companies, 14% on the main pool for chargeable periods beginning on or after 1 April 2026, down from 18%. A period across that date uses a hybrid rate. The special rate pool stays at 6%.

**Can a company claim full expensing on a car?**
No. Cars never qualify for full expensing, the annual investment allowance or the 40% first-year allowance. New zero-emission cars get a 100% first-year allowance to 31 March 2027.

**What is the new 40% first-year allowance?**
A 40% allowance on new main-rate plant and machinery bought on or after 1 January 2026. Unlike full expensing it is allowed for plant bought for leasing, and the remaining 60% goes into the main pool.

**Is the annual investment allowance reduced for a short period?**
Yes. For an accounting period of 9 months it is £750,000. Companies under common control share one allowance.

**Are allowances restricted when a director uses an asset privately?**
Not for a company. Assets a company provides to directors or employees as part of their remuneration are treated as used wholly for the trade; the private-use restriction applies to sole traders and partnerships.

## Sources

- [GOV.UK: annual investment allowance](https://www.gov.uk/capital-allowances/annual-investment-allowance)
- [GOV.UK: full expensing](https://www.gov.uk/capital-allowances/full-expensing)
- [GOV.UK: 40% first-year allowance](https://www.gov.uk/capital-allowances/40-first-year-allowance)
- [GOV.UK: first-year allowances](https://www.gov.uk/capital-allowances/first-year-allowances)
- [GOV.UK: capital allowances on business cars](https://www.gov.uk/capital-allowances/business-cars)
- [GOV.UK: capital allowances rates and pools](https://www.gov.uk/work-out-capital-allowances/rates-and-pools)
- [GOV.UK: disposing of an asset if you claimed full expensing or the 50% first-year allowance](https://www.gov.uk/guidance/disposing-an-asset-if-you-claimed-full-expensing-or-50-first-year-allowance)
- [Finance Act 2026, section 28](https://www.legislation.gov.uk/ukpga/2026/11/section/28)
- [Finance Act 2026, section 29](https://www.legislation.gov.uk/ukpga/2026/11/section/29)
- [Finance Act 2026, section 30](https://www.legislation.gov.uk/ukpga/2026/11/section/30)
- [Capital Allowances Act 2001, section 45S](https://www.legislation.gov.uk/ukpga/2001/2/section/45S)
- [HMRC Capital Allowances Manual, CA23220](https://www.gov.uk/hmrc-internal-manuals/capital-allowances-manual/ca23220)
- [HMRC Capital Allowances Manual, CA23225](https://www.gov.uk/hmrc-internal-manuals/capital-allowances-manual/ca23225)
- [HMRC: changes and issues affecting the Corporation Tax online service](https://www.gov.uk/guidance/changes-and-issues-affecting-the-corporation-tax-online-service)

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