Start with the current-year guide if you need rates and allowances, or use the share-matching guides when you need to understand how a disposal is connected to earlier and later purchases. The broker guides cover the separate practical question of which transaction file to export.
FiscalFox organises its guidance around the sequence used in a UK share calculation: establish the taxable account history, identify the same security across accounts, apply same-day and following-30-day matching, then update the Section 104 holding. Reporting guides explain how the resulting totals can support Self Assessment without presenting the calculator as an HMRC filing service or personal tax advice.
Rate, allowance and matching-rule statements link to GOV.UK or HMRC material, including Helpsheet 284 and the current Capital Gains Tax rates. Each detailed guide states its publication and update dates so readers can distinguish current-year figures from enduring calculation principles.
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Open calculatorCGT basics
Rates, allowances, reporting thresholds, and examples.
Read guideStep-by-step share disposal calculations.
Read guideCurrent rates, allowances and reporting context.
Read guideWhat has been reported before the 28 October Budget, and what it means for you.
Read guideHow the £3,000 annual exempt amount works.
Read guide2026/27 rates and the historical split-year change.
Read guideHMRC share matching rules
How same-day purchases are matched.
Read guideThe anti-avoidance rule for quick repurchases.
Read guideAverage cost pooling for remaining shares.
Read guideUsing, claiming, and carrying forward losses.
Read guideNo-gain/no-loss transfers and inherited pooled cost.
Read guideHow reorganisations affect quantities and pooled costs.
Read guideReporting and SA108
What goes into the Self Assessment capital gains pages.
Read guideHow excess reportable income affects taxable accounts.
Read guideImport a Koinly report with your broker files for one capital gains report.
Read guideSix crypto tax tools checked against HMRC matching rules.
Read guideWhat a real Koinly UK report contains and the settings to check.
Read guideWhat the letter means, how to check your figures and how to correct past years.
Read guideBroker and crypto workflows
Our preferred crypto tax provider, the referral offer and how it fits alongside your share reports.
Read guideFind your statements, upload trade history and calculate gains using UK share matching.
Read guideExport transactions, understand sterling values and fees, and calculate UK share gains.
Read guideFind the right export instructions for your platform.
Read guideHL, IBKR and Trading 212 tax documents compared with the exports you need.
Read guideWhy a dollar profit can be a sterling loss for UK CGT.
Read guideVest-date base cost, sell-to-cover and the 30-day rule for share plans.
Read guideCombine matching securities across investment accounts.
Read guideRecords, supported scope and complex cases.
Read guideCompare portfolio tracking with a specialist UK CGT workflow.
Read guideThe free ukcgt.xyz calculator compared, and when it is enough.
Read guideThe free whatsmycgt calculator compared, and when it is enough.
Read guideOfficial UK tax references
This guide is checked against published GOV.UK and HMRC material. FiscalFox is a calculation tool, not personal tax advice; review unusual transactions with a qualified adviser.