For anyone who held crypto before 2026, 31 December 2025 is the most important date in the entire capital gains tax: the snapshot moment. The value of your portfolio on that day is the starting point for calculating your later capital gains. But how do you still prove, five or ten years from now, exactly what you held back then, and what it was worth? That is what the snapshot certificate is for now.
What is the snapshot certificate?
The snapshot certificate is a PDF document with a CSV attachment that captures your complete portfolio on 31 December 2025, across all your connected wallets, exchanges and CSV imports. Per asset, the certificate documents:
- the quantity you held on the reference date;
- the value in euro at that moment;
- the price source used for that valuation;
- the weighted average starting value that serves as the basis for the capital gains calculation.
The document refers to the relevant legal basis (art. 102 WIB 92) and is framed as an indicative calculation: a tool for you and your accountant, not a compliance certificate.
Versioned: older versions are kept
If you later add a forgotten wallet and generate the certificate again, the old version is not overwritten. Each generation gets a version number and stays available. That way you can always demonstrate what you captured at which moment, and how your file has evolved.
Why this matters
For pre-2026 positions, the capital gains tax uses the market value on 31 December 2025 as the starting value by default (the step-up rule). Anyone who sells within a few years must be able to substantiate that starting value. Exchanges disappear, export formats change and price history becomes harder to reconstruct as time passes. A certificate generated today, with a source reference per asset, is then worth its weight in gold.
Where do you find it?
The certificate is available in two places:
- For accountants: in the client file, under the export options of a paid file. You generate the certificate per client and keep it with the file.
- For users: as a beta feature. Turn on the "beta features" toggle in your settings to generate the certificate for your own portfolio.
Frequently asked questions
Is the certificate an official certificate?
No. It is an indicative calculation based on the data you have supplied. It supports your file towards the tax authorities or your accountant, but does not replace professional advice.
What if my data is not yet complete?
Generate the certificate again after you have connected extra wallets or exchanges. Every version is kept, so you never lose an earlier capture.
Want to know more about the capital gains tax itself? Read how the Belgian capital gains tax on crypto works.