Valuing Crypto in Pounds for Your UK Tax Return

Updated 17 October 2026

General information, not tax advice. We are not HMRC and are not affiliated with it. Check GOV.UK. Last checked against GOV.UK: 17 October 2026. Anything marked expected should be re-checked. Examples use made-up figures. This page contains no affiliate links. Never enter your UTR, National Insurance number or other identifiers on this site.

Short answer: HMRC's manual says many cryptoassets trade on exchanges that don't use sterling, so the value of any gain or loss must be converted into pounds on your Self Assessment return. If a transaction has no sterling value (for example bitcoin swapped for Ether), you must establish an appropriate exchange rate to convert it. Reasonable care should be taken to arrive at an appropriate valuation using a consistent methodology, and details of the methodology should be kept.

What to record

The date and time, tokens, and the sterling value used.
Where the price came from and how you applied it, the same way each time.
Keep the evidence with your other records (records checklist).

Where it matters

Swaps (see same-day and 30-day rules), income received in tokens (crypto income), fees paid in tokens (fee example) and gifts (gifts).

Made-up example

You swap 0.5 BTC for 8 ETH. No pounds change hands, so you pick a sterling price for the swap from one documented source and use the same source and method for all your swaps that year.

FAQ

Does HMRC publish approved rates? Not on the page read.

Will the platform's data (CARF) include sterling values? See what HMRC will receive; for CARF, platforms report fair market value in a single fiat currency at the time of the transaction using a consistent method, and for crypto-to-crypto trades they value both sides after fees (IEIM8000540). That is the platform's reporting valuation; your own return still needs your sterling figures.

What we could not verify

Uncertain. These points were not confirmed on the pages read. A re-check of the GOV.UK CARF pages is planned for 1 December 2026.

Whether HMRC accepts particular price sources (not stated).
Valuation of illiquid or unlisted tokens.
Whether the single fiat currency a platform reports is sterling (IEIM8000530 and 8000540 say "a single fiat currency" only).
The page's review date (not shown).

Sources (official)

GOV.UK (HMRC), Cryptoassets Manual, CRYPTO23000: Cryptoassets for individuals: valuation — https://www.gov.uk/hmrc-internal-manuals/cryptoassets-manual/crypto23000 (read in full 17 October 2026; the manual page shows no review date)
HMRC International Exchange of Information Manual, IEIM8000500 Reporting Requirements (index) and IEIM8000530, 8000540, 8000555, 8000590 — https://www.gov.uk/hmrc-internal-manuals/international-exchange-of-information/ieim8000500 (index and the four linked pages read in full 17 October 2026; no review dates shown)

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