UK Capital Allowances
Pool plant & machinery, compute AIA, WDA and FYA, and produce a CT-feed worksheet
Nothing native computes UK capital allowances in Odoo, so accountants and tax preparers do it in fragile Excel workbooks that break when rates change or a disposal complicates the pool. This app computes capital allowances on plant and machinery directly in Odoo: main, special and single-asset pools, AIA allocation, reducing-balance WDA with period pro-rating, FYA full expensing, small-pools write-off and balancing adjustments. It produces a clean per-period worksheet you feed into your own CT600 process. It is a worksheet and format generator only with configurable HMRC rates; it does not file anything with HMRC.
Key Features
Main, special and single-asset pools
gb.capall.pool models main-rate (18% WDA), special-rate (6% WDA) and single-asset pools, each with a configurable wda_rate, small_pool_limit and aia_eligible flag. _onchange_pool_type sets the standard 18% or 6% rate automatically when you pick the pool type.
AIA allocated to the best additions first
action_compute orders pools highest-WDA-rate first so the Annual Investment Allowance lands on the most beneficial special-rate additions. AIA is absorbed against the prorated annual limit and any overflow spills into the pool balance as aia_claimed and additions_aia.
Reducing-balance WDA with period pro-rating
_compute_pool applies the Writing Down Allowance to the brought-forward value plus additions less disposals, at the pool's wda_rate scaled by period_days/365. _compute_period prorates both the WDA and the aia_limit_prorated for short or long accounting periods.
FYA / full-expensing 100% relief
Assets flagged with relief = fya on gb.capall.asset are claimed at 100% in year as fya_claimed and never enter the pool. AIA and WDA-only additions are handled separately, so each addition gets the relief you select per asset.
Small-pools write-off and disposals
When a pool balance falls at or under its small_pool_limit (default GBP 1,000) the whole balance is written off as WDA. Disposals during the period reduce the pool capped at cost, and a fully disposed single-asset pool produces a balancing allowance or charge via balancing_adjustment.
Brought-forward chaining across periods
_pool_brought_forward reads each pool's carried_forward from the most recent prior finalised computation, so once a period is finalised its closing balances become the next period's opening figures automatically without re-keying.
Per-pool CT-feed worksheet
Each gb.capall.computation.line shows brought_forward, AIA/FYA/pool additions, disposals, AIA/FYA/WDA claimed, balancing adjustment and carried_forward. _compute_totals rolls these into total_allowances, and worksheet_summary returns a headline dict ready to feed your CT600.
Quick-add asset wizard, configurable rates
The gb.capall.add.asset.wizard records an addition (with AIA/FYA/WDA relief) and can recompute open worksheets covering the acquisition date. All HMRC rates and limits (AIA cap, WDA rates, small-pool limit) are fields you set, so the module stays correct year to year. It generates the worksheet only and never files with HMRC.
Use Cases
Screenshots
Add Asset
Assets
Computations
Pools
Why Choose This Module
Compute UK capital allowances on plant and machinery directly in Odoo and produce a clean worksheet you can feed into your CT600 process. This is a worksheet and format generator only — it does NOT file anything with HMRC. All rates and limits are configurable so the module stays correct year to year.
Specifications
- Compatible: Odoo 18.0 / 19.0
- License: OPL-1
- Languages: English
- Author: Pokutsoft
- Dependencies: account
- Support: support@pokutsoft.com
Update date: 2026-07-02