Liquidity pools and impermanent loss: UK tax records
Quick answer: Impermanent loss measures performance against holding the original assets; it is not itself a UK tax deduction. Analyse pool entry, ownership of deposited tokens, LP rights, rewards and exit. The quantities and sterling values on each leg matter more than a dashboard’s profit figure.
Record LP tokens, pool entry and exit, rewards and impermanent loss for UK tax, with current rules separated from proposed April 2027 reform.
What impermanent loss actually compares
A pool can return a different mix of assets from the one deposited. “Impermanent loss” compares that outcome with simply holding the original mix. It does not directly calculate taxable proceeds or allowable costs. A pool position can underperform holding while still producing a taxable gain measured in pounds.
Pool entry and the beneficial ownership question
Under HMRC’s current DeFi guidance, a transfer of beneficial ownership can create a disposal. Inspect what rights the pool receives and what the LP token represents. The presence of a smart contract is not a tax exemption. Save the relevant terms and the GBP values at entry.
Sources: HMRC: making a DeFi loan
Keep principal, receipt tokens and rewards separate
Record assets supplied, the LP position received, any reward token and assets returned at exit. This avoids classifying all pool withdrawals as income or assuming that every receipt is simply a return of original cost.
| Event | Record separately |
|---|---|
| Deposit | Quantity and GBP value of each supplied asset |
| LP receipt | Token ID or position and rights acquired |
| Reward | Asset, quantity, receipt time and character of return |
| Withdrawal | LP rights given up and each asset received |
| Fee | Fee token, value and purpose |
An illustrative mismatch between return and tax
An investor’s pool ends worth £9,000. Holding the original tokens would have produced £10,000, but the starting cost was £6,000. The £1,000 performance shortfall is not automatically an allowable loss. Tax still requires reconstruction of the actual entry, reward and exit events; the final valuation alone cannot supply the answer.
Performance loss is not the tax loss
Illustrative values · not a tax calculation
The pool ends at £9,000 versus £10,000 for holding, from a £6,000 starting cost. The tax calculation still depends on the actual entry, reward and exit events; impermanent loss alone is not a deduction.
Read the chart values
- Starting cost: £6,000. Original investment
- Pool position at exit: £9,000. Actual ending value
- Holding the original tokens: £10,000. Comparison scenario
£1,000 behind holding ≠ a £1,000 tax deduction
Source: HMRC DeFi guidance
Proposed reform is a separate tax-year question
The July 2026 draft addresses certain automated market-making arrangements and proposes relief from 6 April 2027. It does not justify retrospectively removing taxable entries from earlier years. Keep quantities and pool rights now so the conditions can be assessed when the rules take effect.
Frequently asked questions
Can I deduct impermanent loss from crypto gains? +
Not simply as a dashboard metric. Calculate the actual tax events and any allowable losses under the applicable rules.
Does withdrawing from a pool only return my capital? +
The output may include different assets, quantities and rewards. Record those separately and assess the rights surrendered.