2025/26File online by 31 January 2027

    UK capital gains tax calculator for sharesBroker files to capital gains workings.

    Upload your broker history to calculate gains and losses using HMRC share-matching rules. Review the result free, then download your report pack.

    Free calculation. £39.99 report. No sign-up or card to start.

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    FiscalFox calculation preview

    Capital Gains Summary2025/26SA108-ready

    Capital gains summary for tax year 2025/26

    £8,571.56

    Avg. rate: 23.95%

    Taxable Gains

    £35,782.32

    After £3,000 exemption

    Total Gains:£46,811.65Losses:£8,029.33Net:£38,782.32

    Cumulative gains over time

    £0£15,000£30,000£45,000£60,000AprJunAugNovJanMar

    Gains/losses by asset

    -£3,000£0£3,000£6,000£9,000VVNPAABLKJPMBULLMETA: £6,880.40V: £6,125.75UAL: £5,480.30PLTR: £4,975.80VNP: £4,512.60PAY: £4,230.55AA: £3,920.25NUE: £3,745.00BLK: £3,590.25NVDA: £3,350.75APD: £-845.20JPM: £-1,125.35VST: £-1,540.60JII: £-1,988.18BULL: £-2,530.00

    A calculation you can check

    Share disposals matched in HMRC order.

    FiscalFox applies the published share-matching sequence, then shows the proceeds, allowable cost and treatment behind each disposal.

    Matching rules and tax-year allowance applied automatically

    Same-day matching

    Sales matched with acquisitions made that day.

    30-day rule

    Repurchases after a sale checked before the pool.

    Section 104 pool

    Average pooled cost tracked across your holdings.

    Annual exemption

    The allowance for your selected tax year is applied.

    Accumulation fund income (ERI)Calculated automatically for supported funds.

    ERI guide

    No sign-up · No card required

    Calculations and supporting evidence, not personal tax advice.

    See it before you sign up

    See the actual FiscalFox workflow.

    Switch steps to explore the same interface used to import trades, review a calculation and download the report pack.

    Report pack · £39.99 one-time

    The figures for your return. And the evidence behind them.

    Transfer the SA108 figures into Self Assessment, then keep the detailed workings if you or HMRC need to trace a number later.

    Complete the return

    Box-ready totals for listed shares and securities.

    Check every disposal

    Proceeds, allowable cost, gain or loss, and matching rule.

    Keep a defensible record

    Section 104 pool movements and source transactions.

    Pay only when you download

    Your 2025/26 report pack
    PDF + CSV

    SA108 supporting schedule

    Listed shares and securities

    Tax year 6 April 2025 to 5 April 2026

    READY TO TRANSFER

    Box 23

    Number of disposals

    15

    Box 24

    Disposal proceeds

    £102,468

    Box 25

    Allowable costs

    £63,686

    Box 26

    Gains before losses

    £46,812

    Box 27

    Losses in the year

    £8,029

    Estimated Capital Gains Tax

    £8,571.56

    2025/26

    FiscalFox customer reviews

    “Made figuring out capital gains much less of a headache.”

    Greg AndrewTrustpilot review

    Simple pricing

    Calculate first. Pay only for the report.

    See your calculation before deciding. The report pack brings together the figures for your return and the workings behind them.

    On-screen calculation

    Always free
    £0no sign-up required

    Upload your files, combine brokers and check the result before deciding whether you need downloadable records.

    Calculate capital gains
    Combine multiple broker exports
    Review gains, losses and transactions
    See estimated tax on-screen
    Download reviewable report packs

    HMRC report pack

    One-time payment
    £39.99per selected tax year

    Unlock downloadable reports for one selected tax year. Every other tax year is purchased separately, or unlock every tax year to date with priority support for £100.

    Capital Gains Tax Summary (PDF and CSV)
    Detailed SA108 supporting schedule
    Disposal computations and matching workings
    Complete transaction history
    Dividend and interest summary
    Dedicated support with your report pack

    Calculating CGT for clients?

    Use a multi-client workspace with firm billing, working papers and team access.

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    Questions, answered.

    Is it really free to start?

    Yes. Upload your broker export, calculate your gains, and view everything on-screen for free. You only pay if you want downloadable, reviewable SA108 supporting reports.

    Will my broker work?

    FiscalFox has 21 built-in imports: Vanguard, Hargreaves Lansdown, Fidelity, Freetrade, Trading 212, eToro, InvestEngine, Moneybox, Saxo, Interactive Brokers, Robinhood, Revolut, Webull, AJ Bell, Interactive Investor, IG, Morgan Stanley, Charles Schwab, Futu / moomoo, DEGIRO and Lightyear. For other formats, choose Other Broker: if our usual import cannot read the file, a background check uses AI on a few sample rows to work out how, then checks every row before adding your transactions.

    How do I know the numbers are right?

    FiscalFox implements HMRC's published share-matching sequence: same-day matching, the 30-day bed and breakfast rule, and Section 104 pooling. The detailed report traces the cost and proceeds used for each disposal so you or your adviser can review the calculation.

    Is my data secure?

    For supported brokers, CSV and Excel files are processed in your browser session. If our usual import cannot read a file, a background check sends its column headings and a few sample rows to our AI provider, without a separate permission step, and checks the result against every row. Uploaded files are kept privately, normally for 14 days, with the exceptions explained in our privacy policy.

    When do I need to upgrade?

    The free tier lets you calculate and view your gains on-screen. Pay £39.99 only when you want the downloadable PDF and CSV report pack for a selected tax year. Every other tax year requires its own purchase, or you can unlock every tax year to date with priority support for £100.

    Is there a subscription?

    No. The report pack is a one-time £39.99 payment with no recurring charge. You can download the unlocked reports again whenever you need them.

    What happens if my capital gains are wrong on my tax return?

    HMRC can collect extra tax and interest for an error and may charge a penalty depending on the circumstances, behaviour and disclosure. FiscalFox keeps the matching workings behind each disposal so you or your adviser can review the figures before filing.

    Bring your broker history together.

    Review your gains, losses and share-matching workings, then download the records you need for your return.