Common Crypto Pooling Mistakes in the UK (HMRC Examples)

Updated 17 October 2026

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Short answer: HMRC's Cryptoassets Manual (CRYPTO22200, and worked examples CRYPTO22253 and CRYPTO22254) sets out how pooling works. The slips below are things the manual's rules rule out; the list of "mistakes" is our own organisation of those rules, not an HMRC list.

1. Using one pool for all your tokens

HMRC: each type of token needs its own pool, with its own pooled allowable cost. Bitcoin, ether and litecoin means three pools.

2. Pooling NFTs

HMRC: NFTs are separately identifiable, so they aren't pooled and no matching rules apply.

3. Treating same-day trades one by one

Where you acquire and dispose of the same type of token on the same day (same capacity), all acquisitions are treated as a single acquisition and all disposals as a single disposal; the acquired tokens are matched with the disposed ones first. Example (CRYPTO22254, Daniel): two disposals (5,000 for £500; 2,000 for £142) become one disposal of 7,000 for £642; four acquisitions become one of 6,500 for £500. The remaining 500 tokens are a part disposal of the pool: gain £642 - £500 - (£1,000 x 500/8,000 = £63) = £79; the pool falls to 7,500 tokens and £937.

4. Forgetting the 30-day rule

Tokens acquired within 30 days after a disposal are matched to that disposal, not added to the pool, after the same-day rule is applied. If several disposals are involved, acquisitions are matched to the earliest disposal first, and the earliest acquisition first. Example (CRYPTO22253, Rachel): a pool of 2,000 tokens costing £1,000; she disposes of 1,000 for £400 on 31 March and 500 for £150 on 20 April, then acquires 700 (£175), 500 (£100) and 500 (£150) over the next weeks. Gain on 31 March: £400 - £175 - £60 = £165; gain on 20 April: £150 - £40 - £90 = £20; the 200 unmatched tokens (cost £60) go into the pool, which becomes 2,200 tokens at £1,060 (our own 30-day example).

5. Dropping the pooled-cost records

HMRC: you must still keep a record of the amount spent on each type of token and the pooled allowable cost of each pool.

6. Mixing capacities

The same-day and 30-day rules are described for tokens held in the same capacity; trustee or business holdings are separate.

A short check before you file

• One pool per token; NFTs outside pools.
• Same-day first, then 30 days, then the pool.
• Rounding: HMRC's examples round to the nearest pound.
• Pool balances at year-end carry forward (key dates for platform deadlines; reconcile records).

FAQ

Is the order of acquisitions on an exchange enough? Not for HMRC: the matching rules decide, not exchange order.

Do fees go in the cost? See [allowable costs](../crypto-cgt-allowable-costs-exchange-fees-uk/).

What we could not verify

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