UK CGT Calculator for Coinbase

The transaction history CSV from Coinbase.com: profile, then Statements, then Transaction history as CSV. It lists every Buy, Sell, Advanced Trade, Convert, Send, Receive and reward with a Timestamp, Transaction Type, Asset, Quantity, Price Currency, Subtotal, Total and Fees column, and all four header layouts Coinbase has used are recognised. Set the date range from your first purchase to today, not just the tax year: the cost of what you sell comes from your whole buying history.

Yes, once the tax year’s gains from every disposal go above the £3,000 annual exempt amount. HMRC treats cryptoassets as property, not currency, so selling for pounds, swapping one coin for another and spending crypto are all disposals (CRYPTO22100). Buying and holding, or moving coins between your own wallets, is not.

Yes. Converting 0.02 BTC to 0.5 ETH is a disposal of the BTC at its sterling value and a purchase of the ETH for the same amount. The report splits the row into a sell leg and a buy leg, takes the sterling value from the Total column, and both legs join the matching rules like any other trade.

Yes. HMRC applies the share rules to tokens (CRYPTO22200): a disposal is matched first against tokens bought the same day, then against tokens bought in the next 30 days, and the rest against the Section 104 pool at average cost. Each coin is its own pool. In the example the ETH sold on 15 September was bought back by the Convert of 10 October, so the sale is matched bed and breakfast and the pool is untouched.

As miscellaneous income at their sterling value on the day received (CRYPTO21200), listed for SA100 box 17 and added to the coin’s pool at that value, so the same pounds are not taxed twice when the tokens are later sold. Rewards Income, Staking Income, Inflation Reward and Interest payout rows, and Receive rows marked as Coinbase rewards, are all read this way.

They are treated as airdrops (CRYPTO22500): no income on receipt and a nil cost in the pool, so the whole sterling value is a gain when the tokens are eventually disposed of. The example’s 10 ALGO from Coinbase Earn sits in the pool at £0. If HMRC would see a reward as payment for a service, add its value as income by hand.

Not by themselves. A Send is a transfer out of the wallet and a Receive is a transfer in, and neither creates a gain; the tokens simply leave or join your pool at cost. If a Send was really a payment for goods or a gift to someone other than your spouse, that is a disposal at market value (CRYPTO22120), so add it as a sale on the edit page.

Yes. Spending crypto is a disposal at the sterling value of what you bought (CRYPTO22120). Card Spend, Admin Debit and Subscription rows are booked as disposals at the spot value in the file, and a Donation to charity is a no-gain, no-loss disposal.

Into the Total. Coinbase’s Total is what left or reached your GBP balance, so a buy’s cost already includes the fee and spread and a sale’s proceeds are already net of them, which is how HMRC allows them (CRYPTO22150). A fee charged in a third coin is a small disposal of that coin in its own right.

Trades priced in another fiat currency are converted at the HMRC monthly exchange rate for the month of the trade. USDC, USDT and the other dollar stablecoins are treated as US dollars for the conversion, but they are still tokens: a stablecoin you hold is a pool, and swapping into or out of one is a disposal.

A reward or airdrop with an empty Subtotal is looked up at the day’s market price where one is available; otherwise the row is listed with a warning and the missing sterling value can be typed in on the edit page. The report is recalculated as soon as it is saved.

Yes. Upload the files together. HMRC pools by token, not by exchange, so ETH on Coinbase and ETH on Binance are one Section 104 pool and the 30-day rule runs across both. A transfer out of one exchange and into the other is not a disposal.

The cryptoassets boxes introduced on the 2024/25 SA108: 13.1 number of disposals, 13.2 disposal proceeds, 13.3 allowable costs, 13.4 gains before losses and 13.5 losses in the year, plus box 17 of the SA100 for staking income. An earlier year’s SA108 has no cryptoassets section; the same five figures go into its Other property, assets and gains boxes.