German public employee posted to Belgium: where are ETFs taxed in 2026?

A German public employee temporarily posted to Belgium may remain fully taxable in Germany, including on ETF income, if the Belgian exclusion for foreign State officials and the German conditions for extended unlimited tax liability apply. Salary taxation, investment taxation and Belgian stock-exchange tax must be assessed separately. The answer depends on the individual situation.

Figures are illustrative: this article concerns income year 2026, Belgian assessment year 2027 where relevant, and the German 2027 tax year for the advance fund income attributed to that year.

Living in Belgium does not always mean Belgian resident taxation

Consider a typical public employee temporarily assigned from Germany to Belgium who starts investing through a foreign broker. The first question is the employee’s tax status, before considering the account or the ETF.

Ordinarily, establishing a tax domicile in Belgium brings worldwide income within Belgian personal income tax, known as IPP. Registration in the population register creates a rebuttable presumption of residence. FPS Finance explains the residence framework here.

However, article 4, 3° of the Belgian Income Tax Code 1992 (CIR 92) excludes certain officials, representatives and delegates of foreign States and foreign public bodies from IPP. The relevant conditions include:

• A qualifying relationship with a foreign State or public body.

• The nationality and permanent-establishment conditions.

• Services outside a commercial or industrial activity.

• Reciprocity between the countries concerned.

Where the exclusion applies, the person falls within the non-resident framework under article 227 CIR 92, rather than Belgian taxation of worldwide income. Ordinary municipal registration does not, by itself, override that exclusion. The administrative commentary on article 4 describes these conditions.

A posting certificate is useful evidence, but it does not make every overseas public employee eligible. The employment relationship, residence history and supporting documents require examination.

Why German unlimited tax liability can continue abroad

§ 1(2) of the German Income Tax Act (EStG) can maintain unlimited German income-tax liability for German nationals who have neither a home nor habitual abode in Germany, remain employed by a German public-law body and receive remuneration from a German public fund.

A decisive condition is that the country where they live taxes them only on a basis comparable to limited tax liability. The Belgian and German classifications are therefore connected: qualifying for Belgian non-resident treatment can support continued German taxation of worldwide investment income.

This statutory arrangement differs from the optional 90% rule under § 1(3) EStG. These provisions should not be treated as interchangeable routes.

If the Belgian classification changes, continued application of § 1(2) must be reviewed. A change of employer or a move towards permanent settlement can also require a fresh analysis.

Public-sector salary and ETF income follow different rules

The Belgium–Germany tax treaty of 11 April 1967, particularly article 19, addresses remuneration paid from public funds for qualifying public service. It contains nationality conditions and exceptions for certain commercial activities. Article 19 is reproduced by NWB.

For a qualifying German public employee, Germany can retain the taxing right over the salary. That does not establish where unrelated ETF income belongs.

If Belgian resident taxation applies instead, the treaty’s article 4 residence rules become relevant. A permanent home is one of the decisive factors. The salary may remain taxable in Germany while being declared in Belgium as exempt foreign income taken into account for progression; investment income then requires a separate Belgian analysis.

An assignment to an EU institution also does not automatically confer EU staff tax privileges. Articles 12 and 13 of the Protocol on the Privileges and Immunities of the European Union concern qualifying EU officials and other servants. A seconded national expert who remains employed and paid by the national employer must be distinguished from directly employed EU staff.

How Germany taxes accumulating ETFs

An accumulating ETF reinvests income instead of paying it out. Under German investment taxation, this does not necessarily defer every tax charge until sale.

The Vorabpauschale, or advance fund income, can produce an annual taxable amount. For 2026, the base rate is 3.20%. Applying the 70% coefficient gives a base income of 2.24% of the fund value at the start of the year.

For an accumulating fund with no distributions, this amount is limited by the actual increase in value. A year without a positive increase does not produce a positive Vorabpauschale under this simplified example. Purchases during the year require a reduction of one twelfth for each full month before acquisition.

The 2026 Vorabpauschale is attributed to the following tax year, 2027. It should not be confused with income received during 2026 and reported in a return filed during 2027.

For a qualifying equity ETF—for example, a fund maintaining an eligible equity allocation of at least 51%—the 30% partial exemption, or Teilfreistellung, leaves 70% taxable. The standard investment-income rate is 25%, plus a solidarity surcharge of 5.5% of that tax: an effective 26.375% on the taxable portion, before any church-tax adjustment.

The annual €1,000 savings allowance, or Sparer-Pauschbetrag, applies across the individual’s investment income. Interest from other accounts can use up the same allowance.

An illustrative €10,000 ETF calculation

Assume an accumulating equity ETF is worth €10,000 at the start of 2026, is held throughout the year, pays no distributions and increases sufficiently in value for the cap not to reduce the calculation.

This illustrates why a small portfolio can generate a reporting question without generating tax payable. It does not establish that every investor will owe nothing: other interest, distributions, gains and the remaining allowance matter.

When units are sold, the gain is calculated taking account of the applicable partial exemption and previously recognised Vorabpauschalen, to prevent double taxation of the same fund income.

Which German forms may be needed for a foreign broker?

Where a foreign broker does not withhold German investment-income tax, taxable investment income may need to be reported through the German income-tax return. Opening an account alone does not establish that taxable income arose or that a return is mandatory. The income, withholding position and other filing conditions determine the obligation.

The relevant forms include:

• Anlage N for employment income.

• Anlage KAP for relevant interest and other investment income.

• Anlage KAP-INV for investment-fund income not subject to German withholding.

A Freistellungsauftrag can allocate the savings allowance at a participating German bank; unused allowance can also be taken into account through the return where appropriate. If a bank stopped withholding after recording a foreign address, its treatment must be checked against the taxpayer’s actual status.

Annual statements, transaction confirmations, acquisition dates, unit quantities and year-end valuations help establish the calculation. The availability of a broker statement does not guarantee that the German fund-tax calculation has been completed.

Which Belgian obligations depend on residence?

For someone validly excluded from IPP under article 4, 3°, foreign ETF income and foreign savings accounts do not automatically enter the Belgian resident-tax system. In the absence of Belgian-source income giving rise to a filing obligation, a Belgian income-tax return may not be required.

The foreign-account reporting obligations associated with Belgian resident taxation—including reporting to the National Bank of Belgium’s Central Point of Contact and mentioning the account in the annual return—must therefore be assessed by reference to status. For a person subject to those obligations, a newly opened foreign account is generally reported in the following year, in time for the relevant return.

Belgian-source income remains a separate issue for non-residents. Some investment income may be subject to final Belgian withholding; the 30% standard rate is not a universal rate for every savings product.

If Belgian resident taxation applies, the investment review can include:

• 30% taxation of relevant foreign interest, subject to the applicable product rules.

• 30% Reynders tax on the relevant taxable debt component of gains on funds within that regime.

• The 10% capital-gains tax framework from 1 January 2026, including the €10,000 annual basic exemption and its conditions.

• Foreign-account reporting and any applicable stock-exchange tax.

These are distinct rules. The 30% and 10% figures should not simply be added and applied to the same entire ETF gain; the fund composition and the interaction between the regimes must be established.

Belgian stock-exchange tax remains a separate question

The Belgian stock-exchange tax (TOB) cannot be resolved solely by determining where investment income is taxed.

For transactions through a foreign professional intermediary, FPS Finance refers to individuals with their habitual residence in Belgium, unless they can establish that the tax has already been paid. That wording requires a separate assessment for a person excluded from Belgian resident income tax. See the official guidance on TOB through a foreign intermediary.

ETF-related rates include 0.12% and 1.32%, depending on the fund and transaction. They are not interchangeable, and the higher rate should not be assumed to concern sales only.

The application of TOB to this particular category remains a point requiring clarification. A documented clarification of that issue is preferable to treating German income-tax residence as an automatic TOB exemption.

Tax-residence declarations and supporting documents

A broker’s Common Reporting Standard (CRS) self-certification should reflect the person’s established tax residence. Possessing tax identification numbers in two countries does not, on its own, establish tax residence in both.

Where the legal analysis supports Germany as the sole tax residence, the broker’s record should be consistent with that conclusion. Genuine multiple-residence situations must also be reported correctly. Removing a country merely to avoid information exchange is not a substitute for resolving the classification.

A useful review considers the posting terms, employer and payer, tax certificates, residence facts, account entity and exact funds. Written correspondence with the Belgian administration can help clarify the position, including TOB. A previous acceptance of a document should not be presented as a permanent guarantee for different facts or future years.

Which dates need attention?

• German 2026 return: the ordinary self-filing timetable points to 31 July 2027. Because that date falls on a Saturday, the standard weekend adjustment moves the deadline to 2 August 2027. Adviser-assisted returns can have a later deadline; individual notices and extensions must be checked.

• 2026 Vorabpauschale: attributed to 2027, and considered in the return for that tax year.

• Annual records: obtain statements and the necessary 31 December and 1 January fund valuations each year. The base rate changes annually; 3.20% is the figure for 2026.

• Belgian assessment dispute: the general objection period is one year, generally counted from the third working day after dispatch for an assessment sent by post. Check the notification method and the deadline stated on the notice.

• Broker updates: check whether the applicable account terms require a new self-certification within 30 days of a change in tax-residence circumstances, and update the information promptly.

An invitation to file and an actual assessment notice are different documents. A disputed classification should be addressed through the procedure appropriate to the document received.

Frequently asked questions

Do I pay Belgian tax on ETFs just because I live in Belgium?

Not necessarily. A qualifying foreign State official can fall outside Belgian resident income tax, but the conditions require individual assessment and TOB remains a separate question.

Does a German public-sector salary mean all my investments are taxed in Germany?

No. The treaty rule for public-service remuneration and the residence rules governing investment income must be considered separately.

Do accumulating ETFs avoid annual German tax?

No. A Vorabpauschale can arise even without a cash distribution; the amount depends on the annual base rate, performance, acquisition timing and fund classification.

How much German tax could a €10,000 equity ETF generate?

Using the 2026 assumptions above, the amount after the 30% partial exemption is €156.80 before the savings allowance. A fully available €1,000 allowance can eliminate the resulting tax, but other investment income changes that calculation.

Will Revolut automatically complete my German ETF tax reporting?

That should not be assumed. The relevant account entity, withholding arrangements and available tax documents must be checked; a foreign fund account may require Anlage KAP-INV.

Is a seconded national expert automatically taxed like an EU official?

No. Remaining employed and paid by a national public employer is different from becoming an EU official covered by the Protocol’s staff provisions.

Sources

• Belgian residence: FPS Finance, Coming to Belgium: tax return and presumption of residence.

• Articles 4, 3° and 227 CIR 92: Fiscosearch, Commentary on article 4 and Commentary on article 26, referring to non-residents under article 227; Forum for the Future, Tax-domicile exception and non-resident return dispensation.

• § 1(2) and § 1(3) EStG: Steuerschroeder, Unlimited and limited German income-tax liability. Also referenced: the Federal Ministry of Finance’s 2018 Income Tax Handbook, section 1a; that section is distinct from § 1(2).

• EU Protocol, articles 12 and 13: Forum for the Future, Belgian tax-return obligations of EU officials.

• Secondment status: European Economic and Social Committee, Rules on the secondment of national experts. These are institution-specific rules, cited for the distinction between national experts and EU staff.

• Belgium–Germany treaty of 11 April 1967: NWB reproductions of article 19, public-service remuneration and article 4, tax residence; Wohnsitzausland, Discussion of articles 18, 19 and 23.

• German ETF taxation: SJB, ETF taxes, savings allowance and returns; Beatvest, Reporting ETFs and Anlage KAP-INV; Deutschland-Rechner, 2026 Vorabpauschale calculation; Steuertipps, Explanation and calculation of the Vorabpauschale.

• Foreign accounts: Test-Achats, Reporting a foreign account to the National Bank and in the tax return.

• Belgian capital-gains taxation: BNP Paribas Fortis, The capital-gains tax in ten questions.

• Stock-exchange tax: FPS Finance, TOB through a foreign intermediary.

• Broker tax information: Revolut, Investor-related tax information and Updating tax information.

This article explains a general framework and is not a personalised tax opinion. Tax rules, rates and filing arrangements can change each year. The correct treatment depends on the exact employment status, residence facts, investment products and relevant tax year.

Need tax advice tailored to your situation?

Have a similar situation? Befiscal has already handled files like this one. To get a written tax analysis tailored to your own figures and situation, click the “Ask your question” chat button on the right of this page: our assistant takes over, gathers the information needed and guides you through to your personalised written analysis.