Gain and tax bridge
How the gross gain is reduced by losses and allowance before the CGT estimate.
Amount
Capital Gains Tax Calculator
Estimate UK Capital Gains Tax across one or more disposals using proceeds, allowable costs, losses, annual exempt amount, asset types, and taxable income.
Estimated CGT£6,3782026/27 across 1 disposal
Taxable gain£28,500After losses and £3,000 allowance
After-tax position£25,12220.2% effective rate on listed gains
CGT rate split
The taxable gain split across basic, higher, or relief-rate CGT treatment.
Taxable gain
Gain by disposed asset
Each listed disposal shown as your share of gain or allowable loss.
GainLoss
Tax by asset type
Estimated CGT split by asset-rate category after the simplified allocation.
Estimated CGT
Disposed assets
Asset 1investment or other asset; your proceeds £75,000; allowable costs £43,500£31,500
Tax year gains
Number of disposals1
Your share of disposal proceeds£75,000
Listed gains before losses£31,500
Losses from listed disposals£0
Net gain or loss from listed disposals£31,500
Losses and allowance
Current-year losses availableLosses from listed disposals plus other same-year losses£0
Current-year losses used£0
Brought-forward losses used£0 left unused in this estimate£0
Total losses used£0
2026/27 annual exempt amount£3,000
Annual exempt amount available£0 already used£3,000
Taxable gain after allowance£28,500
CGT estimate
Taxable income before gainsAfter Personal Allowance and reliefs£30,000
Basic-rate band remaining£7,700
Gain taxed at basic CGT rate£7,700
Gain taxed at higher CGT rate£20,800
Gain taxed at relief rate£0
Estimated Capital Gains Tax22.4% effective rate on taxable gain£6,378
Rate allocation
investment or other asset£28,500 taxable; £7,700 basic, £20,800 higher, £0 relief£6,378
Reporting checks
Your share of disposal proceeds£75,000
Self Assessment proceeds thresholdFor 2023/24 onwards£50,000
Proceeds threshold checkMay need reporting if in Self Assessment
Tax due checkTax estimated
Assumptions
Calculation notes
- Uses the selected 2026/27 annual exempt amount and Capital Gains Tax rates.
- Taxable income before gains should be income after Personal Allowance and Income Tax reliefs, before adding these gains.
- Gains and losses are aggregated across listed disposals for the selected tax year.
- Current-year losses are deducted from same-year gains before the annual exempt amount. Brought-forward losses are then used only to reduce remaining gains down to the available annual exempt amount.
- Where mixed asset types are listed, the model allocates reductions to higher-rate gains first for a practical planning estimate.
- Does not model spouse transfers, private residence relief, lettings relief, chattels rules, EIS/SEIS reliefs, non-resident property reporting, foreign income and gains regime, carried interest, crypto pooling, share matching, or HMRC payment deadlines.
- This is a planning estimate, not tax advice.
Disposal logic
How gains are grouped and taxed
Capital gains are calculated asset by asset first, then brought together so allowances and rates can be applied transparently.
Asset-by-asset method
Each disposed asset is calculated from disposal proceeds less acquisition cost, buying costs, improvement costs and selling costs, adjusted for ownership share.
The calculator pools taxable gains by asset type, applies the selected tax-year annual exempt amount, then estimates basic/higher/additional rate exposure using other taxable income.
CGT pathsale proceeds - allowable costs -> gain; gains - annual exemption -> taxable gains; taxable gains x CGT rates -> estimated CGT
Multiple disposals
Example: more than one disposed asset
- Asset 1: shares or fund disposal
- Asset 2: residential property disposal
- Other taxable income: entered by user
Result: The output separates investment, residential and relief-rate assumptions so the tax estimate is easier to audit.
Different asset types can use different CGT rates, so one blended percentage can hide important detail.
What can change the tax
- The estimate does not decide relief eligibility or reporting requirements for every circumstance.
- Losses, spouse transfers, Private Residence Relief, business relief and timing rules can materially change the answer.
Content reviewed: 7 September 2026.
Guide
Capital Gains Tax Calculator notes
Model a UK Capital Gains Tax estimate across disposals of investments, residential property, or qualifying business relief gains using selectable tax-year assumptions.
Choose the rules year that matches the scenario you are checking.
Review the calculation notes where rules, tax years, thresholds, or eligibility affect the result.
FAQs
Capital Gains Tax Calculator FAQs
What is the Capital Gains Tax Calculator for?
Model a UK Capital Gains Tax estimate across disposals of investments, residential property, or qualifying business relief gains using selectable tax-year assumptions.