Declaring a foreign broker account: the NBB register and box XIII

Two obligations, not one

A Belgian resident who opens an account at a broker established abroad — DEGIRO in the Netherlands, Interactive Brokers in Ireland, Trade Republic in Germany — takes on two distinct reporting duties. They are easy to conflate, and each is satisfied in a different place:

• a one-off registration of the account with the Central Point of Contact (CPC) kept by the National Bank of Belgium (NBB);
• an annual mention of the account on the personal income tax return, in box XIII.

Neither replaces the other. Registering with the National Bank does not exempt the account from the return, and putting it on the return does not register it with the Bank. Both are owed, for the same account, by the same person.

What makes an account "foreign"

The test is where the account is held, not the currency it trades in or where the shares themselves are listed. An account at a broker established outside Belgium is a foreign account, even if it only ever holds euro and European stock.

That line separates the platforms a Belgian investor typically uses. DEGIRO, Interactive Brokers, Trade Republic and BUX are established abroad and produce a foreign account. Bolero, Keytrade, Belfius Re=Bel, BNP Paribas Fortis, MeDirect and other Belgian intermediaries do not — the account sits in Belgium, and neither obligation below is triggered by holding it.

A securities account counts. The Report to the King of the royal decree of 23 June 2019 says so expressly: although for the purposes of the CPC law a securities account is a "financial contract" rather than an "account", it does fall within the definition of a foreign account — "a securities account opened abroad must therefore be declared to the CPC".

A branch flips the test, in both directions. An account opened in Belgium at the Belgian branch of a foreign institution is not a foreign account: that branch reports it to the CPC itself, and declaring it a second time would serve no purpose. Conversely, an account opened at the foreign branch of a Belgian institution is one. That clarification comes from the same Report to the King, which is the official commentary on the decree — it does not appear on the FPS Finance's public-facing page, which stops at "any account with a financial institution located abroad". If you check that page after reading this, it will seem to say the opposite.

What counts, then, is where your account is held. Several brokers have opened a Belgian branch without moving existing accounts into it: a branch registered in Belgium is not enough to conclude that your account sits there, and opening a branch does not retroactively move an account already opened elsewhere. The country printed on your own statement, on the other hand, settles it.

A power of attorney over someone else's foreign account, without being a holder of it, is treated differently from ownership: on the current reading it does not by itself create the registration duty. Ownership — sole or joint — is what does.

The one-off registration with the National Bank

The Central Point of Contact is a register the NBB keeps of the accounts and financial contracts Belgian residents hold. Registering a foreign account there is a one-time act, not an annual one.

The timing follows the return. The registration has to be in place at the latest by the time the tax return that first mentions the account is filed. An account opened this year is registered around the same filing, not in some separate season of its own. That is the text of article 307, §1/1 of the CIR 92 itself: the details have to be reported to the central point of contact "at the latest at the same time as the return is filed".

Two nuances come with that timing. The obligation falls away if the details were already reported in an earlier assessment year — which is what makes the registration a one-off act rather than an annual one. And a late registration is still owed: the NBB asks you to make it anyway, the report simply being treated as late.

What the register asks for is identifying information rather than balances: the account number (the IBAN where there is one), the name of the institution and its country, and the year the account was opened. A later change — a closure, a new account — is reported the same way, which is why the "one-off" is better read as "once per account" than "once per lifetime".

How it is filed is online, at cappcc.nbb.be, with itsme® or your electronic identity card — the only two means of identification the NBB's own guidance names. It is a National Bank channel, separate from MyMinfin and from the tax return itself; the NBB sets out the procedure on its CPC page.

The paper form still exists, and it is exacting: in block capitals, signed by hand, accompanied by a double-sided copy of the identity document — without which the report is refused — and sent to the National Bank of Belgium, Central Point of Contact, boulevard de Berlaimont 14, 1000 Brussels. The NBB refuses anything sent by email, including the scan of a signed form.

The annual line on the return: box XIII

Separately, the personal income tax return carries the account every year it exists. The relevant part is box XIII, whose section A — "Foreign accounts" carries, for assessment year 2026 (2025 income), code 1075-89. There is no separate partner code: the same code covers both spouses or legal cohabitants who file the return together. Securities accounts and cash accounts fall under the same section, which covers accounts of every kind — there is no separate code for a brokerage account.

What the section asks for often surprises people, because it asks for far less than they expect. You tick "Yes", then give, per account:

• the holder's surname and first name;
• the country where the account was opened;
• and you tick a second box: have the account details required by law been reported to the NBB's Central Point of Contact?

Neither the account number nor the name of the institution appears on the return. Those two go to the CPC only. The return does no more than name the holder and the country, and record that the register has been served — which is the clearest way to see how the two obligations fit together: the second tick box points at the first.

Section B is a different subject — certain individual life-insurance contracts taken out abroad — and is not what a brokerage account belongs in.

Two points are worth stating flatly, because both catch people out.

It is annual, and it is independent of income. The account is mentioned for every year it existed, whether or not it paid a dividend or realised a gain in that year. The mention is about the account, not about what it earned.

A code holds for one year only. 1075-89 is read off the preparatory document and the explanatory notes to the assessment year 2026 return published by the FPS Finance. Codes and their wording are set anew each year: the return you are actually filing — its own labels and its instructions — is what governs, not a code quoted from a previous year.

The details each broker actually gives you

It is the register that asks for the detail — the institution, its country and the account number; the return asks only for the holder and the country. The details below therefore serve the CPC registration first. Each broker surfaces them differently, and the identifier that names your account is not always the IBAN you use to fund it. As currently published:

Broker	Account held at	Identifier that names the account	Where you find it
DEGIRO	flatexDEGIRO Bank SE, Frankfurt — the legal form changed from AG to SE on 30 December 2025, so "AG" is an out-of-date name. Country: see the caution below. BIC generally BIWBDE33XXX.	Your DEGIRO account number, plus the linked cash IBAN where one is shown.	In the platform under Deposit / withdraw → SEPA bank transfer, and on the periodic statements under Activity / Documents.
Interactive Brokers	Interactive Brokers Ireland Ltd, Dublin — Ireland.	Your account number — the U-number (e.g. U1234567). IBKR issues a U-number, not a personal IBAN.	Client Portal under Settings; the U-number also heads every Activity Statement under Performance & Reports.
Trade Republic	Trade Republic Bank GmbH, Berlin — Germany. BIC TRREDEFFXXX.	Your personal German IBAN (DE…).	In the app under Profile → account details, and on the transfer and settlement documents.
BUX	BUX B.V., Amsterdam — Netherlands (part of ABN AMRO; assets custodied at ABN AMRO Clearing Bank).	Your depot number — the identifier BUX itself tells Belgian clients to declare.	On the monthly tax statement BUX issues, and in the app's funding details. BUX publishes a dedicated Belgian-resident declaration guide.

Three cautions sit inside that table, and they are why the rule is "read it off your own documents" rather than "copy the row above".

The address and the country do not follow the same rule. The NBB asks for the address of the institution's registered office, not the branch's — but the country it asks for is the one where the account was actually opened, and the two can diverge. The example the NBB itself gives is plain: a securities account opened at the Paris branch of a German stockbroker is declared with the German head office address and the country France.

That is exactly why the table above gives no country for DEGIRO. The entity is German and its registered office is in Frankfurt; but where a Belgian client's account is actually opened — German head office or Dutch branch — is not established by any published source we have been able to verify. The country printed on your own statement is the answer, and it outranks any inference drawn from the platform's flag.

The account number is not the funding IBAN. For Interactive Brokers the IBAN shown in the deposit instructions is a pooled client-funds account used to route money in; the thing that identifies your account is the U-number. Where the register asks for the account number, that is the more faithful entry.

Entities and codes move, and the BICs above are not from an official source. A broker can change banking partner, re-domicile, or merge — flatexDEGIRO did move from AG to SE at the end of 2025. BICs circulate through online directories rather than through any public register we have been able to consult, and the NBB gives the right method anyway: the BIC is "generally shown on account statements". Read it off your own rather than copying the row above.

What leaving it out costs

The applicable fine is the one in article 445, §1 of the CIR 92 — "a fine of €50 to €1,250" for any infringement of the Code — whose scale is set by article 229/1 of the AR/CIR 92. It rises with the rank of the infringement:

Nature of the infringement	1st	2nd	3rd	4th	Subsequent
Circumstances beyond the taxpayer's control	None	—	—	—	—
Without bad faith or intent to evade tax	€50	€125	€250	€625	€1,250
With bad faith or intent to evade tax	€1,250	€1,250	€1,250	€1,250	€1,250

The counter resets if no infringement has been penalised in the four preceding assessment years.

One point is worth stating because the opposite is so often read: the text sets a fine "for any infringement" and the scale is graduated by rank, with no explicit multiplier per account or per year. Paragraph 2 of the same article does provide for a fine "per year and per legal construction not mentioned" — but that per-unit wording exists for legal constructions and is absent for accounts. The figures of €6,250, of €1,250 to €25,000, or of €50,000 to €1,000,000 that you sometimes come across belong to other paragraphs, or to a law aimed at reporting institutions — not at an account holder.

Where this sits next to the tax itself

This is a reporting duty, and it stands apart from the taxes a foreign broker leaves for you to settle. The stock-exchange tax (TOB), the 30% withholding on foreign dividends, and — since 2026 — the tax on realised capital gains are each computed and filed on their own terms. The box XIII mention and the NBB registration do not calculate any of them. They record that the account exists; the tax lines are a separate reckoning, covered in their own guides.

What ties the two together is the same fact that makes a foreign broker convenient and a Belgian return more work: no one else files this for you. A Belgian bank registers your Belgian account and withholds as it goes. A broker abroad does neither, so the register entry and the box XIII line are both yours to make.

Belfolio assembles the cross-broker record those lines are drawn from — which account held what, where it was established, and what each position earned — rather than leaving it spread across three statements that never meet.

Always verify your figures

Belfolio computes and presents these amounts for information only. This is not tax advice. Verify them, and your own reporting obligations, with the FPS Finance, the National Bank or your accountant before filing.