Your Belgian investment taxes, computed and declaration-ready.

Upload your broker exports. Belfolio consolidates your realized gains, applies the 31/12/2025 step-up value and the €10,000 exemption, and gives you the figures to report in your tax return.

Brokers supported today

  • Interactive Brokersyou file it yourself
  • DEGIROyou file it yourself

Bolero, Keytrade, Trade Republic and Saxo follow. An unrecognised export tells you exactly which columns we found.

10%
Belgian rate on gains realized from 1 January 2026.
€10,000
Annual exemption per taxpayer — reclaimable only through your tax return.
€50 / week
Late TOB filing fine (capped at €2,600), plus 7% interest per year.

The calculation

The three rules nobody gets right by hand.

Every figure is computed parcel by parcel, with the line that produced it shown alongside.

The 31/12/2025 value

For anything bought before 2026, your taxable base is the last closing price of 2025 — not what you paid. On a long-held position the gap is large, and it works in your favour.

Exemption and loss offset

The annual exemption and your loss offsets exist only through the tax return. We compute what is actually owed, and what is reclaimable from each broker.

TOB deadlines

If your broker does not withhold the stock exchange tax, we group your trades by period and show the payment deadline, public holidays included.

The difference

A number you can defend.

You sign the return. So you have to be able to explain every amount on it.

Every amount is itemised

For each sale: purchase date, quantity, the acquisition value used and the rule that chose it. Totals are exactly the sum of the lines shown.

No bank connections

Your file is parsed during the request and never saved. No account, no storage, no access to your accounts.

FR, NL and EN

The whole application and every guide exists in all three languages — including DEGIRO exports, whose column headers change with your interface language.

How it works

  1. 1

    Upload your broker export, going back to your first purchase.

  2. 2

    We apply the 31/12/2025 value, the annual exemption and the ten-year rule, parcel by parcel.

  3. 3

    You get the amounts to report, the reasoning behind each line, and your TOB deadlines.

Frequently asked questions

Answers come from the official texts and the sources listed on our methodology page.

Does the capital gains tax apply to me?
It applies to gains realized from 1 January 2026 on financial assets: shares, ETFs, bonds, funds, derivatives and crypto.
My broker already withholds the tax. Do I still have to file?
Yes, if you want anything back. The €10,000 exemption and your loss offsets exist only through the tax return — your broker does not know your overall position.
What happens to shares I bought before 2026?
The acquisition value used is the last closing price of 2025, not what you paid. Your actual purchase price may be used instead if it is higher and evidenced, until 31 December 2030.
How does the €10,000 exemption work?
Once per taxpayer per year across all brokers — not once per account. If a broker withheld tax while the exemption covered your gain, the difference is reclaimable.
What if I use several brokers?
That is exactly the case Belfolio is built for. No broker sees your trades elsewhere, and gains and losses are netted at the level of the taxpayer.
What happens to my file?
It is parsed during the request and never written to disk. The public calculator asks for no account and no email address — that is only needed for the PDF summary.

See your figures in three minutes.

The on-screen result is free and needs no account.

Tax guides for Belgian investors

Answers to the questions Belgian investors actually ask about capital gains tax, TOB and dividends.