Reconcile UK capital-allowance pool additions and disposals

Obtain the prior return's capital-allowance calculation and bring forward each closing tax pool separately. Tie the amount to the filed version or explain a later amendment. Accounting net book value is a useful reconciliation reference, but it is not the opening tax written-down value simply because both schedules concern the same equipment.

HMRC's calculation starts with the prior pool balance, adds qualifying expenditure, deducts relevant disposal values and then applies the allowance. Build that movement record before calculating a deduction. Identify the business, accounting period and tax regime so the reviewer knows which dates and pool rules govern the schedule.

For every addition, retain the asset description, invoice, acquisition terms, business use and expenditure date. Ask the preparer to confirm the pool and any separate relief claim. Do not send all purchases to the main pool automatically: special-rate and single-asset treatment can require different calculations.

Track expenditure relieved through annual investment allowance, full expensing or another first-year allowance alongside the pool schedule. An immediate deduction does not make the acquisition history irrelevant. The eventual disposal may require that history, and a future preparer should be able to tell which part of the original cost entered a pool and which part received another treatment.

Record the item, date, purchaser, proceeds and the original tax treatment. Identify gifts, private use, insurance recoveries and connected-party transactions for review. HMRC's disposal guidance uses different valuation rules in specified circumstances, and the ordinary disposal-value deduction is generally capped at original cost. A book gain or loss is not the pool movement.

Disposals after full expensing or the 50% first-year allowance have specific balancing-charge rules. Keep those assets identifiable instead of subtracting every sale from an undifferentiated pool. Where only part of the cost received the relief, provide the original claimed proportion so the preparer can split the disposal treatment correctly.

The main writing-down allowance changed from 18% to 14% on April 1, 2026 for Corporation Tax and April 6, 2026 for Income Tax. HMRC requires a hybrid rate where the accounting period spans the relevant change date. Retain the date calculation rather than carrying an old rate forward in a workbook heading.

As a simplified movement example before the allowance, a £28,000 opening pool plus £9,000 approved additions less £4,000 approved disposals leaves £33,000. The preparer must still determine the correct rate, period adjustment and actual claim. Do not use this arithmetic to bypass first-year relief, private-use or other applicable rules.

Reconcile the allowance actually claimed to the return and calculate the closing balance on that basis. Explain balancing charges, balancing allowances and any decision to claim less than the available allowance. Preserve the final pool file with the asset-level history and review notes. Next year's opening schedule should come from this approved tax calculation rather than a newly exported depreciation report.