What missing crypto history means for your tax report.

A common crypto tax problem is selling an asset on one platform even though the original purchase happened somewhere else. If the report cannot see the purchase, it cannot reliably calculate cost basis for that disposal.

What is an unmatched disposal?

An unmatched disposal happens when the report sees a sale, swap, or outgoing taxable event, but the FIFO lot history does not contain enough acquired quantity to match it. A responsible report should flag this instead of pretending the cost basis is zero or inventing a number.

Common causes

• You imported only one exchange, but bought the asset on another exchange.
• You transferred crypto from a wallet without uploading the wallet history.
• You imported only the tax year, but acquired the asset in a prior year.
• The exchange export omitted older rows, fees, or conversion legs.
• The asset ticker changed or wrapped-token history is incomplete.

How to fix it

Export full history from every relevant platform. If an asset was moved from self-custody, include the wallet or prior exchange data where possible. If a manual reconstruction is needed, document the source, date, quantity, and CHF value clearly.

How it should appear in a report

The report should show which assets have missing acquisition history, how much quantity is unmatched, and which proceeds were excluded from realised gain calculations. That tells you exactly what needs attention before submitting.