Section 104 pool: how a UK company tracks the cost of its bitcoin

How it works

HMRC's Cryptoassets Manual says that where tokens are dealt in without identifying the particular tokens disposed of, they are pooled under section 104 of the Taxation of Chargeable Gains Act 1992. Each type of token has its own pool. Each purchase adds the number of tokens and their allowable cost to the pool. Each disposal takes out a proportion of the pooled cost, in line with the share of the pool sold.

Companies have two exceptions, which are different from the rules for individuals. Tokens bought on the same day as a disposal are matched with that disposal first. And if a company buys tokens and then disposes of tokens of the same type within ten days, the disposal is matched with the purchases from the previous nine days, oldest first, before the pool. The pooled cost is untouched by those matched purchases.

Why it matters for a company

The pool means the cost of a particular coin, or a particular UTXO, does not decide the gain for a UK company. That simplifies record keeping in one way and makes it stricter in another: every acquisition and disposal must be recorded, in pounds, at the time, using a consistent method, so the pool can be rebuilt. HMRC's manual also expects businesses to keep the amount spent on each type of token as well as the pooled cost.

The ten day rule matters for treasury policy. A company that sells and buys back within a few days, for example while rebalancing, may find its disposals matched with the new purchases instead of the pool, which changes the gain.

The US has no pool for bitcoin. A US corporation tracks basis by unit, wallet by wallet or account by account under Revenue Procedure 2024-28, and the regulations default to first in, first out within each wallet if units are not specifically identified. See cost basis.

Common mistakes

• Using the individual 30 day rule instead of the company ten day rule.
• Leaving fees out of the pool records.
• Pooling different token types together.

Related

• Cost basis
• UTXO
• Fair value
• Consolidation
• Company tax on bitcoin
• All glossary terms

Sources

Primary sources only. Each link was checked on 9 November 2026. Rules change, so confirm the current version with your adviser.

1. HMRCCRYPTO41350: Corporation Tax on chargeable gains, pooling and the same day and ten day rules
2. HMRCCRYPTO41250: Corporation Tax on chargeable gains, what counts as a disposal
3. HMRCCRYPTO41300: Corporation Tax on chargeable gains, allowable costs
4. HMRCCRYPTO40100: Conversion to sterling and accountancy
5. IRSRevenue Procedure 2024-28: allocating unused basis to wallets and accounts (PDF)
6. Cornell LII (unofficial copy of the CFR)26 CFR 1.1012-1(j): digital assets, specific identification and the first in, first out default