TaxKey review

Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

TaxKey is UK tax reporting software for investors and high earners with investment-heavy Self Assessment needs. It imports broker and trading-platform transactions, calculates capital gains and investment income, and supports foreign shares, dividends, RSUs and tapered pension allowance calculations. The product also prepares Self Assessment returns for review and submission to HMRC. It is aimed at individuals, accountants and organisations handling UK investment tax reporting rather than broad personal-tax workflows.

Its strongest area is the depth of its investment calculations. TaxKey supports UK share-pooling, 30-day-rule and bed-and-breakfast calculations, alongside automated CSV ingestion and transaction standardisation. Foreign-asset and RSU support adds coverage for more complex portfolios, while auditable gain and loss calculations provide a review trail. The Individual Self Assessment plan includes broker imports, automatic capital gains and investment-income calculations, tapered pension allowance support and an HMRC-compliant return ready for submission. TaxKey states that it does not provide personalised tax advice.

The paid plan structure extends beyond individual filing. Accountant Pro adds multi-client portfolio and tax reporting, bulk data imports, collaboration tools, advanced compliance reporting, priority support and account management. White Label & API provides access to UK investment tax calculations, plus white-label or co-branded interface options and zero-knowledge hosting options. The product runs in the cloud through web and API access, with email support. TaxKey is a strong fit for UK investors with complex capital gains or professionals managing multiple investment-tax clients; people seeking a general personal-tax tool should choose a broader alternative.

TaxKey pros and cons

• Where it wins
  • Imports transactions from any broker and standardises CSV data
  • Handles share-pooling, 30-day rules, foreign assets and RSUs
  • Prepares auditable returns for review and HMRC submission
• Where it doesn't
  • Focused on investment-heavy UK Self Assessment workflows
  • Paid product with no free plan
  • Support is provided through email

TaxKey fact sheet, pricing and score →

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Last updated 7 Oct 2026 · How we research and update