Crypto loan interest in the UK can be taxable as income or as a disposal for Capital Gains Tax. Use the decision checklist to classify receipts and convert each item to GBP at the receipt time.
Cryptocurrency loans & interest: HMRC tests
HMRC looks at the legal nature of the receipt to decide tax treatment. Read the contract and check who keeps market risk.
Legal basis and guidance
HMRC treats crypto under ordinary tax law and the Cryptoassets Manual. See the HMRC Cryptoassets Manual for technical guidance.
The legal test asks whether the event is payment for work or an alienation of a chargeable asset.
Keep careful timestamps for every receipt and conversion.
Practical checklist HMRC applies
Check these points to classify a receipt. Labelling, ownership and who bears price risk are central.
- Was the receipt labelled as interest, reward or repayment?
- Did ownership of the asset change?
- Who bore price risk after the event?
These checks form the decision flow used later.
E‑E‑A‑T signal: common error
The most frequent error is assuming every DeFi reward counts as a disposal. Many guides skip contractual and economic tests and misclassify rewards.
When interest becomes a disposal
A receipt is a disposal when it results in a change to the asset held. Swapping rewards into another token or receiving a different asset after collateral liquidation are disposal events.
Examples that trigger disposal
Receiving token A and swapping it into token B counts as disposal of token A. Collateral liquidations that return a different asset also trigger disposal.
These disposals are taxable events for Capital Gains Tax under TCGA 1992.
Examples treated as income
Contractual interest paid on top of an unchanged holding usually counts as income. Periodic interest credited in the same token, with no change in principal, often sits in Income Tax.
Keep careful timestamps for every receipt and conversion.
Case example
A common case: a lender gets weekly auto‑compounded rewards in the same token on Aave. The lender then swaps weekly rewards into stablecoins.
The compounding element increases the cost basis. Each stablecoin swap is a disposal and may create a gain or loss.
How to calculate tax and convert to GBP
Convert crypto receipts to GBP at the market rate when the receipt occurs. Use that GBP value as the taxable income amount or as proceeds for CGT.
Converting receipts to GBP
Use the market rate at blockchain confirmation or when the platform credits the account. Record source, date, time and the exchange used.
Example: 0.5 ETH received on 01/04/2025 when ETH = £2,000 gives GBP 1,000 of taxable income.
Worked income example
0.5 ETH interest received on 01/04/2025 converted at £2,000 equals GBP 1,000. If the taxpayer is a basic‑rate payer at 20 percent, tax due on that income is GBP 200.
Record the rate and source to defend the figures if HMRC queries them.
Worked CGT example
Lent 1 BTC originally bought for GBP 10,000. After loan events the lender receives 0.8 BTC (GBP 6,000) and 0.1 ETH (GBP 200).
Proceeds equal GBP 6,200. Deduct allowable costs and pooled cost basis for the gain calculation under TCGA 1992.
For a CGT example, assume you bought 1 BTC for £10,000 and then received 0.2 BTC which you swapped for GBP producing proceeds of £3,000. Apply the matching rules and the proportionate cost basis.
Cost attributable to 0.2 BTC = 0.2 × £10,000 = £2,000. Gain = £3,000 − £2,000 = £1,000.
Deduct the tax‑year annual exempt amount and apply the applicable CGT rate. Crypto gains usually pay 10% for basic‑rate band gains and 20% for higher‑rate band gains.
Record the source rate, timestamp and txID so the SA108 entries can be supported if HMRC enquires.
Platforms differ in how they record interest and rewards. CeFi platforms often provide CSV exports and interest summaries.
DeFi requires on‑chain evidence and event logs.
Download monthly statements and interest reports from platforms such as Binance, Coinbase or Nexo. Reconcile each statement line with on‑chain txIDs where possible.
Keep screenshots of account pages showing balances and interest terms.
DeFi protocol steps
Export wallet transactions and event logs from Etherscan or the protocol subgraph. For Aave or Compound, capture lending and reward events with timestamps.
Auto‑compounding requires treating each compounding event as an incremental receipt for records.
Convert each crypto receipt to GBP at the timestamp when the blockchain confirms the receipt or when the platform credits the account. Use the same exchange source across the tax year and record URL, time and rate for each conversion.
Table: CeFi vs DeFi reporting
| Feature |
CeFi examples |
DeFi examples |
| Statement availability |
Monthly CSV reports (Binance, Nexo) |
On‑chain logs; protocol subgraphs |
| Evidence ease |
High; central records |
Medium; needs aggregation |
| Typical tax character |
Interest often shown explicitly |
Rewards may require classification |
Keep careful timestamps for every receipt and conversion.
Process: From Receipt to Report
- Capture txID and timestamp
- Convert amount to GBP at that timestamp
- Classify as income or disposal using checklist
- Enter figure on Self Assessment (SA100/SA108 where needed)
Keep 6 years of records
(HMRC minimum)
Platform reports show fields that need mapping to CSV columns. CeFi providers like Nexo or Binance usually show a labelled 'Interest' or 'Earn' line with date, asset and amount.
A typical CSV line reads: 2025‑04‑01, Nexo, BTC, 0.0100, interest. Treat that line as income at the GBP value on the credited timestamp.
Aave auto‑compounds balances on‑chain and requires on‑chain evidence. The evidence is a sequence of on‑chain supply and interest accrual events.
For example, supplying 1,000 DAI and receiving 10 DAI in auto‑compounded interest across three events requires recording three timestamps and three GBP conversions.
Compound uses cTokens where interest is realised on redemption. The taxable point for many users is when underlying tokens are redeemed for a different asset or GBP.
Map each platform field (date, txID, asset, amount) to the CSV template columns below. Keep a screenshot of the platform's 'interest' or 'rewards' page to reconcile exported lines to logs.
Decision tree: income or disposal?
Use simple yes/no steps to classify receipts. The decision tree reduces error and supports a defensible position if HMRC queries figures.
Binary checkpoints
Step 1. Is there a contractual interest payment? If yes, treat as income.
Step 2. If no, did the event change the asset held? If yes, treat as disposal.
These two checkpoints resolve most cases.
Edge checkpoints for DeFi
Who bears market risk, and whether the reward auto‑compounds, both matter. Auto‑compounding increases cost basis when later disposing.
Rewards automatically swapped into other tokens create disposals at the swap time.
Keep careful timestamps for every receipt and conversion.
Legal strategies and compliance risks
Standardise records and FX sources across the tax year. That practice reduces audit risk and shows a consistent methodology to HMRC.
This is a lawful compliance strategy, not avoidance.
Mitigation that works in practice
Standardising FX sources works well in theory, but platforms and on‑chain timestamps differ in practice. Reconciling differences by keeping platform and exchange records provides an audit trail.
The approach cuts errors in Self Assessment figures.
Red flags and when to seek help
Large automated DeFi positions, cross‑border lending, and custodied third‑party platforms increase complexity. Contact a specialist tax adviser if positions include multiple jurisdictions or complex synthetics.
The evidence points to rising HMRC focus on crypto.
HMRC published targeted guidance and updated its materials in subsequent years. Enforcement activity has increased.
For novel structures, a formal opinion from a tax professional creates a defensible record and may lower inquiry risk.
Complex positions involving DeFi, cross‑border lending or large balances benefit from tailored advice from a specialist crypto tax adviser.
This guidance does not apply to businesses or traders operating as a trading company, to non‑UK tax residents whose tax affairs lie elsewhere, or to purely fiat loans with no crypto element. For complex DeFi stacks, cross‑border lending, or HMRC enquiries, seek specialist advice before filing.
Frequently asked questions
Are crypto loans taxable in the UK?
They can be taxable as income when interest or rewards are received. They can be taxable as a disposal for Capital Gains Tax when the asset changes.
Use the decision checklist to determine which applies and convert receipts to GBP at the receipt timestamp.
Do you pay taxes on a crypto loan?
Borrowing alone usually does not create a taxable receipt for the borrower. Lenders who receive interest generally report taxable income.
Collateral movements can cause disposals and trigger CGT.
Do you pay tax on crypto interest?
Yes. Crypto interest usually creates taxable income at the time it is received. Report the GBP value on Self Assessment and keep conversion proof and txIDs.
How do I convert interest into GBP for tax?
Convert using a reliable market rate at the time the blockchain confirms the receipt or when the platform credits the account. Record the exchange, timestamp and URL used so the figure is auditable by HMRC.
What records should be kept for HMRC?
Keep a CSV of date, txID, platform, asset, amount, GBP rate source, GBP rate timestamp, GBP value, event type and fees. Retain platform statements, screenshots of terms, and on‑chain links for six years.
Are DeFi rewards taxed differently to CeFi?
The same tax rules apply but classification differs by mechanics. CeFi often labels payments as interest; DeFi may show rewards without labels, so classification depends on economic effect and contract terms.
When should capital gains be reported?
Report gains on disposals during the tax year and use the SA108 Capital Gains summary when required. If total gains exceed the annual exempt amount, report and pay within HMRC deadlines.
Stablecoin interest is normally taxable in the UK as income at the GBP equivalent at the time of receipt. If you receive 100 USDC and the GBP equivalent at receipt is £80, include £80 in Self Assessment.
The mechanics are the same whether the receipt originates in CeFi or DeFi, but CeFi often supplies a GBP column directly while DeFi requires conversion with a consistent FX source.
Your next step
Export all platform statements and on‑chain logs for the current tax year. Populate the CSV template with each receipt and convert every item to GBP at the receipt time.
Classify each event using the decision checklist and then fill Self Assessment boxes accordingly.
Date_utc,txid,platform,asset,amount,gbp_rate_source,gbp_rate_timestamp,gbp_value,event_type,fee_gbp,notes
2025-04-01,0xabc...,Aave,ETH,0.5,Kraken,2025-04-01T12:34:56Z,1000,interest,0,"auto-compounded"
If tax figures look material or positions include cross‑border elements, a specialist tax adviser provides a tailored calculation, helps decide on disclosure, and ensures the correct Self Assessment boxes are used.
