If you have ever held cryptoassets and assumed that HMRC's visibility was limited, 2026 is the year that assumption breaks definitively. The UK is implementing the OECD's Crypto-Asset Reporting Framework (CARF) and updating the Common Reporting Standard (CRS) to extend automatic exchange of information into the crypto space. The practical effect: HMRC will receive your trading history from major exchanges, both UK and international, with very few hiding places left.
How HMRC taxes crypto today
Before diving into the new reporting, a quick recap of the rules that have been in force for years but which many crypto holders have not engaged with:
- Capital Gains Tax applies on disposal of cryptoassets held for investment. The annual exempt amount is now £3,000 (down from £12,300 a few years ago), so most active traders generate reportable gains.
- Income Tax applies to mining rewards, staking yields, airdrops received for services, and trading carried on as a business (rare but possible for high-frequency traders).
- Disposal includes selling for fiat, swapping one token for another, using crypto to buy goods or services, and gifting (other than between spouses).
- Section 104 pooling applies to most acquisitions, similar to share pooling, with special rules for same-day and 30-day "bed and breakfasting" transactions.
CARF: what changes from 2026
The Crypto-Asset Reporting Framework imposes reporting obligations on Reporting Crypto-Asset Service Providers (RCASPs) — essentially exchanges and certain wallet services. They will report annually:
- The aggregate purchase and sale amounts for each customer, by asset.
- Transfers to and from external wallets.
- Customer identification details (name, address, jurisdiction of residence, tax identification numbers).
The first reporting period in the UK is the 2026 calendar year, with reports due to HMRC by 31 May 2027. HMRC will then exchange this information with other CARF jurisdictions on a reciprocal basis. The list includes the EU, the US, Canada, Australia, Singapore, the UAE, and over 50 other jurisdictions.
The Let Crypto Campaign — voluntary disclosure window
Anticipating CARF, HMRC has run targeted "nudge letter" campaigns at suspected crypto holders since 2021 and offers a voluntary disclosure facility specifically for cryptoasset under-declarations. Disclosing voluntarily — before HMRC writes to you — typically reduces penalties to between 0% and 20% of the unpaid tax. Once HMRC has the CARF data and writes to you first, penalties can run to 100% for deliberate behaviour, plus interest.
Common errors we see on crypto returns
- No return at all because "I never cashed out to GBP". Token swaps are disposals. A BTC-to-ETH trade in 2021 was a CGT event.
- Cost basis calculation errors. Section 104 pooling with multiple acquisitions across years requires careful tracking.
- DeFi income misclassified as capital. Yield from staking, lending and liquidity provision is typically income on receipt.
- Wallet-to-wallet transfers mistakenly treated as disposals (they are not, if both wallets belong to the same person).
- Lost or stolen tokens claimed as losses without the necessary "negligible value" claim or theft documentation.
The data trail HMRC will see
Even before CARF, HMRC has issued statutory information notices to Binance, Coinbase and other major exchanges and obtained user lists for UK residents. From 2026, the data flow is automatic and comprehensive. If you have transacted on a CARF-reporting exchange in 2026, HMRC will know:
- Your total fiat-equivalent purchases and sales.
- External wallet addresses you have moved tokens to.
- Any KYC details you provided.
Mixing services, privacy coins and self-custody do not break this chain entirely, but they create gaps that HMRC interprets unfavourably in the absence of contemporaneous records.
What to do now
- Reconstruct your full history. Pull complete transaction exports from every exchange and wallet you have used.
- Use specialist crypto tax software (Koinly, CoinTracking, Recap). Allow time — historic reconstructions for active traders can take days, not hours.
- File amended Self Assessment returns for any year where you under-declared. The "discovery" window is four years for careless behaviour, twenty for deliberate.
- Use the voluntary disclosure route if you have material under-declarations. Initiating a disclosure protects against the harshest penalty bands.
- Document your 2025 and 2026 activity meticulously so that, when the CARF report arrives at HMRC, it reconciles to your return.
Special situations
NFTs are taxed as cryptoassets. Wrapped tokens (wBTC, stETH, etc.) are generally treated as disposals on wrapping and unwrapping under HMRC's current guidance, though this remains contested. Hard forks are zero-cost acquisitions; airdrops vary based on whether they were earned. Each of these has nuance worth getting right.
If you are unsure where you stand, the worst thing you can do is wait. Book a confidential 30-minute crypto review with PushDigits and we will assess your position and recommend a disclosure strategy if needed. We integrate the crypto work with your overall Self Assessment and tax planning, so the resulting return is consistent across all sources. Detailed enquiries via the contact page.