Crypto glossary
Crypto tax software
Crypto tax software imports transactions from exchanges and wallets, matches buys and sells, and calculates gains, income and tax reports.
These tools connect to exchanges through read-only API keys or CSV exports and read public blockchain addresses directly. They classify each transaction as a trade, transfer, income or fee, apply a cost-basis method allowed in the user's country, such as FIFO in Spain, and produce reports formatted for local tax forms, including US Form 8949 or the data needed for the Spanish income tax return. Some also generate the information for Spain's Modelo 721.
For active traders and DeFi users, software is close to essential: thousands of swaps, rewards and fees would be unmanageable by hand. Tax advisers specialising in crypto typically use the same tools as a starting point.
Results are only as good as the data. Transfers between one's own wallets are often misread as sales, DeFi and bridge transactions are frequently misclassified, and missing history from closed exchanges breaks the cost-basis chain. Users remain responsible for what they file, so reviewing flagged transactions and keeping exports is important. Granting only read permissions to API keys limits security risks.
Example
A Spanish user connects three exchanges and two wallets to a tax tool. It flags 40 unmatched transfers, which she labels as moves between her own accounts before exporting the gains report for her return.