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UK guide · 7 minute read

Your Solana wallet on a 2025/26 HMRC Self Assessment return.

If you swapped, sold or spent tokens from a Solana wallet between 6 April 2025 and 5 April 2026, those are disposals HMRC may want on your return. This guide covers the dates, the records HMRC says to keep, and how to get the wallet’s transactions into Koinly so it can do the sterling calculations.

The dates for the 2025/26 return

Sources: GOV.UK, Self Assessment tax returns: deadlines; GOV.UK, Capital Gains Tax rates and allowances.

What HMRC counts as a disposal

HMRC’s guidance says you may need to pay Capital Gains Tax when you dispose of tokens by:

• selling them,
• exchanging them for a different cryptoasset (on Solana, that includes a swap such as SOL to USDC on Jupiter),
• using them to pay for goods or services,
• giving them away, unless the gift is to your spouse, civil partner or a charity.

If your total gains for the tax year are above the tax-free allowance, you must report them and pay. Tokens you receive from staking, lending or liquidity pools are treated differently: HMRC counts them as income, not a gain, when you aren’t trading.

Sources: GOV.UK, Check if you need to pay tax when you sell cryptoassets (updated 5 October 2026); GOV.UK, Check if you need to pay tax when you receive cryptoassets.

The records HMRC asks for, and what the file covers

For each type of token, HMRC says to keep a record of every transaction. Here is how that list lines up with a SolLedger export and with the work your tax software does.

Source: GOV.UK, Records you must keep.

Pooling, and why one year is not always enough

UK gains use pooling. Each token type has one pool with an average cost. Two rules come first: tokens bought on the same day as a sale are matched to it, and tokens bought in the 30 days after a sale are matched to it next. Only then does the pool apply. Koinly calls this method Share Pooling and uses it by default for UK users.

That has two practical effects on a single-year file:

• The pool starts with your first purchase. If the wallet held SOL before 6 April 2025, Koinly needs the earlier years too, or the average cost will be wrong.
• The 30-day rule crosses the year end. A sale on 1 April 2026 can be matched with a buy on 20 April 2026, which is in the next tax year. If you sold in the last 30 days of the year, import the next period as well.

Sources: HMRC Cryptoassets Manual, CRYPTO22200: pooling; Koinly Help Center, Cost basis method.

Step by step

1. Open SolLedger with the 2025/26 UK tax year selected and paste your wallet’s public address. You never connect the wallet.
2. Run the free preview and check the rows look like your activity.
3. Pay 3 USDC and download the CSV. It runs from 6 April 2025 00:00 UK time (5 April, 23:00 UTC) to the same moment in 2026.
4. Repeat for earlier years if the wallet held tokens before April 2025. Calendar years are fine for that; Koinly merges and removes duplicates.
5. In Koinly, set your country to the United Kingdom, add the wallet and import the file. Check the cost basis method shows Share Pooling.
6. Use Koinly’s figures, in pounds, in the cryptoasset section of your return. HMRC says that section is on returns from 2024/25 onwards.

Questions