How to compute uk-capital-gains-sa108 for United Kingdom, tax year 2025: rates, thresholds, and step-by-step rules with primary-source citations.
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Accountant-reviewed. Reviewed by James Power on Jun 3, 2026. Review does not create a client relationship and is not a guarantee for any specific taxpayer or transaction.
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All assets — basic rate
18%TCGA 1992 s.1H/1I
All assets — higher rate
24%TCGA 1992
BADR qualifying gains (2025-26)
14%TCGA s.169H
BADR qualifying gains (2026-27)
18%Finance Act 2025
BADR lifetime limit
£1,000,000TCGA 1992
2024-25 individuals
£3,000TCGA 1992
2025-26 individuals
£3,000TCGA 1992
2025-26 trustees
£1,500TCGA 1992
Last months always exempt
9 monthsTCGA s.222-226
Letting relief cap
£40,000TCGA s.223
Garden/grounds exempt
Up to 0.5 hectaresTCGA s.222
Deadline
60 days from completionTCGA 1992
Late reporting penalty
£100 initialTMA 1970
Rendered from the facts database · facts last reviewed Jun 3, 2026. General reference only — confirm with a qualified professional before acting.
Reviewed against the cited tax authorities by James Power on 2026-06-03.
Items flagged for further clarification are tracked separately and excluded here.
This block is generated from verified skill_facts — edit the facts, not the prose.
Section 1 Quick Reference
| Field | Value |
|---|---|
| Country | United Kingdom |
| Tax | Capital Gains Tax (CGT) |
| Currency | GBP only |
| Tax year | 6 April to 5 April |
| Primary legislation | Taxation of Chargeable Gains Act 1992 (TCGA 1992) |
| Supporting legislation | Finance Act 2024 (rate changes from 30 Oct 2024); Finance Act 2024 BADR/IR two-step uplift; Autumn Budget 2024; TCGA ss. 1H, 1I (rates); TCGA s. 222-226 (PPR); TCGA s. 169H-169S (BADR); TCGA ss. 104, 106A, 107 (share matching) |
| Tax authority | HMRC |
| Filing portal | HMRC Self Assessment Online |
| Filing deadline | 31 January following the tax year (SA return); 60 days for UK residential property (CGT on UK Property return) |
| SA108 form | Capital Gains Tax Summary supplementary pages to SA100 |
| HMRC crypto guidance | HMRC CG12100+ (Cryptoassets Manual) |
| Validated by | Verified by James Power on 2026-06-03 |
| Skill version | 2.0 |
Three-Year Headline Rate Comparison
| Item | 2024-25 | 2025-26 | 2026-27 |
|---|---|---|---|
| Annual Exempt Amount (individuals) | £3,000 | £3,000 | £3,000 |
| AEA (trustees) | £1,500 | £1,500 | £1,500 |
| Non-residential CGT (basic / higher) | 10% / 20% pre-30 Oct 2024; 18% / 24% from 30 Oct 2024 | 18% / 24% | 18% / 24% |
| Residential property CGT (basic / higher) | 18% / 24% | 18% / 24% | 18% / 24% |
| BADR rate (up to £1m lifetime) | 10% | 14% | 18% |
| Investors' Relief rate | 10% | 14% | 18% |
| Investors' Relief lifetime limit | £10m → £1m (dropped 30 Oct 2024) | £1m | £1m |
| Carried interest (fund managers) | 28% | 32% (transitional from Apr 2025) | Reclassified as trading income (income tax rates; no CGT treatment) from Apr 2026 |
All rates frozen across the three-year window unless explicitly shown changing.
6 April 2024 to 29 October 2024
| Asset type | Basic rate | Higher / additional rate |
|---|---|---|
| Residential property (non-PPR) | 18% | 24% |
| Other assets (shares, crypto, non-residential) | 10% | 20% |
| BADR qualifying gains | 10% | 10% |
| Investors' Relief qualifying gains | 10% | 10% |
30 October 2024 to 5 April 2025
| Asset type | Basic rate | Higher / additional rate |
|---|---|---|
| All assets (residential and non-residential) | 18% | 24% |
| BADR qualifying gains | 10% | 10% |
| Investors' Relief qualifying gains | 10% | 10% |
2025-26 rates
| Asset type | Basic rate | Higher / additional rate |
|---|---|---|
| All assets | 18% | 24% |
| BADR qualifying gains | 14% | 14% |
| Investors' Relief qualifying gains | 14% | 14% |
| Carried interest | 32% (transitional) | 32% (transitional) |
2026-27 rates
| Asset type | Basic rate | Higher / additional rate |
|---|---|---|
| All assets | 18% | 24% |
| BADR qualifying gains | 18% | 18% |
| Investors' Relief qualifying gains | 18% | 18% |
| Carried interest | Reclassified — taxed as trading income at income tax rates + Class 4 NIC. NO CGT treatment. | — |
AEA Historic and Frozen Range
| Tax year | Individuals | Trustees |
|---|---|---|
| 2022-23 | £12,300 | £6,150 |
| 2023-24 | £6,000 | £3,000 |
| 2024-25 | £3,000 | £1,500 |
| 2025-26 | £3,000 | £1,500 |
| 2026-27 | £3,000 | £1,500 |
The £3,000 AEA is frozen across the full three-year planning window.
Two structural changes apply from 6 April 2026 that materially shift planning for business owners and fund managers:
BADR and Investors' Relief rates rise to 18% (the second step of the Finance Act 2024 two-step uplift: 10% → 14% → 18%). The lifetime limit remains £1m. After this step, BADR/IR effectively offer only a 6-percentage-point discount over the standard 24% higher rate — much narrower than the historic 14-point gap (10% vs 24%). Pre-6 April 2026 disposals at 14% remain valuable; clients with imminent exits should weigh acceleration.
Carried interest reclassified as trading income. From 6 April 2026, carried interest received by private fund managers is no longer a capital gain. It is taxed as trading income — subject to income tax (up to 45%) and Class 4 NIC. The 32% CGT rate that applied transitionally in 2025-26 is withdrawn. There is no CGT treatment available from this date.
Conservative Defaults
| Ambiguity | Default |
|---|---|
| Unknown acquisition cost | STOP — cannot compute gain |
| Unknown whether PPR applies | Do NOT apply PPR (taxable in full) |
| Unknown residency status | STOP — affects CGT liability |
| Unknown whether basic or higher rate | Compute at higher rate (conservative) |
| Unknown whether disposal is connected persons | Treat as connected (market value rule applies) |
| Unknown disposal date around 30 Oct 2024 | Use post-30 Oct rates (conservative) |
| Unknown disposal date around 6 Apr 2025 / 6 Apr 2026 BADR step | Use the LATER (higher) BADR rate |
CGT rates depend on where the gain falls relative to the basic rate band:
Share Matching Rules priority order
| Priority | Rule | Reference |
|---|---|---|
| 1 | Same-day acquisitions | TCGA s. 105(1) |
| 2 | Acquisitions within 30 days AFTER disposal (bed and breakfasting rule) | TCGA s. 106A |
| 3 | Section 104 pool (average cost of all shares held) | TCGA s. 104 |
UK share disposals follow strict matching rules in this priority order:
The Section 104 pool is a rolling average cost of all shares of the same class in the same company:
Crypto CGT event treatment table
| Event | CGT Treatment |
|---|---|
| Selling crypto for fiat (GBP, USD, etc.) | Disposal — gain/loss computed |
| Exchanging one crypto for another | Disposal of the first crypto |
| Using crypto to pay for goods/services | Disposal at market value |
| Gifting crypto | Disposal at market value |
| Transfer between own wallets | NOT a disposal |
| Receiving airdrop (no consideration given) | Acquisition at zero cost |
| Mining/staking rewards | Income when received; acquisition cost = income value |
| DeFi lending | Depends on terms — may or may not be disposal |
From 2024-25, SA108 includes dedicated crypto boxes:
Partial PPR Relief table
| Period | Treatment |
|---|---|
| Periods of occupation as main residence | Exempt |
| Last 9 months of ownership (regardless of occupation) | Always exempt (deemed occupation) |
| Periods of absence due to employment (up to 4 years) | Exempt if resided before and after |
| Periods of overseas employment (any length) | Exempt if resided before and after |
| Letting relief | Up to £40,000 if part of PPR was let as residential accommodation |
| Garden/grounds | Exempt up to 0.5 hectares (or larger if appropriate to the property) |
BADR feature table
| Feature | Detail |
|---|---|
| Lifetime limit | £1,000,000 (unchanged across 2024-25, 2025-26, 2026-27) |
| Rate — pre-6 Apr 2025 | 10% |
| Rate — 6 Apr 2025 to 5 Apr 2026 | 14% |
| Rate — from 6 Apr 2026 | 18% |
| Qualifying assets | Shares in a trading company (5% holding, 2-year ownership, officer/employee); sole trader/partnership business |
| Claim deadline | 1st anniversary of 31 January following tax year of disposal |
| Interaction with AEA | AEA used first; BADR applies to remaining gain |
Investors' Relief feature table
| Feature | Detail |
|---|---|
| Lifetime limit | £10m before 30 Oct 2024; £1m from 30 Oct 2024 onwards |
| Rate — pre-6 Apr 2025 | 10% |
| Rate — 6 Apr 2025 to 5 Apr 2026 | 14% |
| Rate — from 6 Apr 2026 | 18% |
| Qualifying conditions | Newly issued ordinary shares in unlisted trading company; held ≥3 years; subscriber must not be an employee/officer |
Investors' Relief tracks BADR on rates but applies to external investors (non-employees) in qualifying unlisted trading companies.
Carried interest treatment table
| Period | Treatment |
|---|---|
| Pre-Apr 2025 | 28% CGT rate |
| 6 Apr 2025 onwards (transitional) | 32% CGT rate |
| From 6 Apr 2026 | Reclassified as trading income — taxed at income tax rates (up to 45%) plus Class 4 NIC. No CGT treatment. |
Carried interest is out of scope for SA108 from 2026-27 — it migrates to SA103 (self-employment) / employment pages depending on structure.
60-Day Property CGT reporting feature table
| Feature | Detail |
|---|---|
| Applies to | Disposals of UK residential property by UK residents (where CGT is due) and ALL disposals by non-residents |
| Deadline | 60 days from completion of the sale |
| Form | CGT on UK Property return (online HMRC service) |
| Payment | CGT due with the 60-day return (payment on account) |
| SA return | Still required — CGT on UK Property return is reported on SA108, with credit for CGT already paid |
| Penalty for late reporting | £100 (initial); further penalties accrue |
| Exemption from reporting | If no CGT due (e.g. full PPR relief applies) — reporting still recommended |
Loss Rules table
| Rule | Detail |
|---|---|
| Current year losses | Must be set against gains of the same year (even if this wastes the AEA) |
| Brought-forward losses | Used only to reduce gains to the AEA level (not below) |
| Carry forward | Indefinite |
| Carry back | Only on death (to the 3 previous tax years) |
| Connected person losses | Can only be set against gains from disposals to the same connected person |
| Negligible value claim | Treat asset as disposed of and reacquired at negligible value — creates an allowable loss |
| Claim deadline | 4 years from end of tax year |
Disposal patterns table
| Pattern | Treatment | Notes |
|---|---|---|
| SHARE SALE, STOCK SALE, BROKER PAYOUT | Disposal — compute gain/loss | Match using share matching rules |
| PROPERTY SALE, SOLICITOR COMPLETION FUNDS | Disposal — compute gain/loss | 60-day reporting required for residential |
| BINANCE WITHDRAWAL, COINBASE SELL, CRYPTO SALE | Disposal — compute gain/loss | Match using crypto pool rules |
| GIFT OF SHARES, GIFT OF PROPERTY | Disposal at market value | Gift = disposal at MV for CGT |
| LIQUIDATION DISTRIBUTION, COMPANY WIND-UP | Disposal — capital distribution | May qualify for BADR if trading company |
| EIS DISPOSAL, SEIS DISPOSAL | Check relief conditions | May be exempt if held ≥3 years |
Acquisition cost evidence table
| Pattern | Classification |
|---|---|
| SHARE PURCHASE, BROKER BUY | Acquisition cost (add dealing fees) |
| STAMP DUTY, SDLT | Incidental acquisition cost |
| SOLICITOR FEES (acquisition) | Incidental acquisition cost |
| SURVEY, VALUATION (on purchase) | Incidental acquisition cost |
| RENOVATION (capital improvement) | Enhancement expenditure |
Input: Sold 1,000 shares on 15 November 2024 for £25,000. Section 104 pool average cost: £10 per share. No same-day or 30-day matching. Basic rate taxpayer with £5,000 unused basic rate band.
Computation:
Proceeds: £25,000
Cost (1,000 × £10): £10,000
Gain: £15,000
Less AEA: £3,000
Taxable gain: £12,000
Rate (post-30 Oct): 18% basic / 24% higher
Basic rate portion: £5,000 × 18% = £900
Higher rate portion: £7,000 × 24% = £1,680
Total CGT: £2,580
Input: Sold 0.5 BTC on 1 February 2025 for £20,000. BTC Section 104 pool: 2 BTC at average cost £8,000 per BTC. No same-day or 30-day match.
Computation:
Proceeds: £20,000
Cost (0.5 × £8,000): £4,000
Gain: £16,000
Less AEA: £3,000
Taxable gain: £13,000
Rate (post-30 Oct): 18%/24% depending on income
Input: Owned house 10 years. Lived in it for 6 years, let it for 4 years. Total gain £200,000.
Computation:
Exempt (PPR): 6 years + last 9 months = 6.75 years
Total ownership: 10 years
PPR fraction: 6.75/10 = 67.5%
PPR exempt: £200,000 × 67.5% = £135,000
Chargeable: £200,000 - £135,000 = £65,000
Letting relief: lower of (a) £40,000, (b) PPR exempt amount, (c) chargeable letting gain = £40,000
Chargeable after letting relief: £65,000 - £40,000 = £25,000
Less AEA: £3,000
Taxable: £22,000
Scenario: Sole trader sells qualifying trading business for a gain of £900,000 (all within £1m BADR lifetime limit; no other gains in year; AEA available).
The same disposal is modelled across three completion dates to show the cost of delay:
Gain: £900,000
Less AEA: £3,000
Taxable BADR gain: £897,000
BADR rate change table
| Completion date | Tax year | BADR rate | CGT |
|---|---|---|---|
| 5 April 2025 | 2024-25 | 10% | £89,700 |
| 5 April 2026 | 2025-26 | 14% | £125,580 |
| 6 April 2026 | 2026-27 | 18% | £161,460 |
Real cost of delay:
Planning implication: where a sale is commercially imminent and BADR-qualifying, completing before 6 April of the relevant rate-step year materially reduces tax. Conversely, where the deal is dependent on commercial readiness, the cost of slipping a tax year should be quantified for the client before completion is timed.
Input: Sole trader sells business for £500,000 gain. Owned >2 years. Claims BADR. Disposes before 6 April 2025.
Computation:
Gain: £500,000
Less AEA: £3,000
Taxable: £497,000
BADR rate: 10% (pre-6 Apr 2025)
CGT: £49,700
Within £1M lifetime limit. Deduct £500,000 from remaining lifetime allowance.
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Review status
Accountant-reviewed
Reviewed by a named licensed practitioner against the stated sources, as general reference material.
Accountant-reviewed · Guide version 20
Reviewed by James Power · 3 June 2026
A named accountant reviewed this complete Guide version within the stated scope. It is not a guarantee.
View review record →Other United Kingdom computations in the OpenAccountants Tax Library.
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