ChainTax

One price. One tax year. Done.

Pay once, download your HMRC-ready report. No subscriptions. No per-transaction fees. No surprises.

Import or scan 200 transactions free — pay only when you download.

Pay once · 14-day refund · Secure payment via Stripe

2024/252025/262026/27

File 2025/26 before 31 Jan 2027.

Light

£49/tax year

Up to 2,500 transactions

Exchange-led — Coinbase, Binance, Kraken with a wallet or two.

  • Up to 2,500 transactions
  • Coinbase, Binance, Kraken CSV import
  • 33 DeFi protocol classifiers
  • Section 104 pooling + same-day & B&B matching
  • PDF + CSV report download
  • Show Working — full audit trail per disposal
  • SA108 box mapping + Box 51 split-year auto-compute
  • Loss carry-forward across tax years
Most popular

Active

£99/tax year

Up to 10,000 transactions

DeFi-active — swaps, LPs, staking, bridging across multiple chains.

  • Up to 10,000 transactions
  • Coinbase, Binance, Kraken CSV import
  • 33 DeFi protocol classifiers
  • Section 104 pooling + same-day & B&B matching
  • PDF + CSV report download
  • Show Working — full audit trail per disposal
  • SA108 box mapping + Box 51 split-year auto-compute
  • Loss carry-forward across tax years

Over 10,000 transactions?

We'll run a Concierge sync for you — quote-first, no commitment.

Concierge details

Questions? hello@chaintax.co.uk — we typically reply within a few hours.

Bundle deal

Filing 2025/26 & 2026/27?

Get both tax years in one checkout and save.

Save £19

Light

£79/ 2 years

£98 separately

Save £29

Active

£169/ 2 years

£198 separately

Bundle covers 2025/26 and 2026/27. Already purchased one year? Buy each year individually to upgrade.

What ChainTax doesn't do yet

No tax tool is perfect. Here's what ChainTax cannot yet handle automatically — and what you should check manually or discuss with your accountant.

  • •Aave interest (aTokens) accrues via balance changes rather than individual transactions, so it doesn't appear in your transaction history. For now, add aToken interest manually as an income event — automatic detection via daily balance snapshots is on the roadmap.
  • •Lido stETH rebase rewards happen at the protocol level and rarely appear as transactions in your wallet. Add them manually as income for now — automatic detection via daily balance snapshots is on the roadmap.
  • •Deposits into Aave, Compound, Yearn, EigenLayer, and similar fixed-ratio lending or staking protocols are treated as transfers, not disposals — your cost basis carries to the receipt token (aToken, cToken, vault share). HMRC's strict reading (Cryptoassets Manual CRYPTO61620) could treat these as deemed disposals at deposit; pending NGNL legislation is expected to confirm the no-gain-no-loss treatment ChainTax applies today, but if you want strict-reading compliance, override the deposit event manually.
  • •Some protocols return ETH via internal calls (Nexus Mutual, Rocket Pool, cbETH). We catch most of these automatically; when we can't, we flag the event for your review.
  • •Five EVM chains supported: Ethereum, Arbitrum, Optimism, Base, and Polygon. Other chains (Solana, Avalanche, etc.) are not yet covered.

Full detail: How it works → Known limitations

Common questions

Which tax rules does ChainTax apply?

All three HMRC matching rules: same-day, 30-day bed-and-breakfast, and Section 104 pooling (average cost basis). Bridging and ETH→WETH wrapping are correctly treated as non-disposal transfers. 2024/25 split-year CGT rates (10%/20% before 30 Oct, 18%/24% after) are applied per disposal.

What do I get for free?

Import exchange CSVs or connect your wallets and classify up to 200 transactions. View your full report summary, every classification with confidence ratings, and Show Working for each disposal. PDF and CSV downloads require a purchase.

Can I upgrade later?

Yes. Buy Light now and upgrade to Active later — you only pay the difference. Your data stays intact.

What if a classification looks wrong before I file?

You can manually edit transactions before downloading your report, including the tax type and notes for anything that needs an override. If you are unsure, email hello@chaintax.co.uk and we will help you check it before you file.

Why per tax year, not a subscription?

You file once per year, so you pay once per year. Each purchase covers one UK tax year (6 April to 5 April). No recurring charges, no auto-renewals.

Which chains and exchanges are supported?

On-chain wallet scanning for Ethereum, Arbitrum, Optimism, Base, and Polygon. CSV import from Coinbase, Binance, and Kraken. Centralised exchange rows from Koinly (including non-EVM exchange trades) are fully supported as manual entries. On-chain activity from non-EVM chains isn't classified automatically.

How does this compare to an accountant?

A UK crypto-specialist accountant typically charges £300+ to manually classify 50 transactions. ChainTax classifies thousands automatically — exchange trades and DeFi — with full working shown, from £49.

What happens if HMRC changes the SA108 format?

We update ChainTax each tax year to match the latest HMRC guidance. When HMRC introduced dedicated crypto boxes (13.1–13.8) on SA108 for 2024/25, we shipped support on day one — including the split-year CGT rate change. Future format changes will be handled the same way.

Further reading

SA108 crypto boxes 13.1–13.8 for 2024/25 explainedUK crypto tax 2024/25 — the complete guideHMRC nudge letters: what to do if you get one

Switching from another tool?

Koinly vs ChainTaxCoinTracker vs ChainTaxRecap vs ChainTax