Before you start

National register number
A determination of whether you are a Belgian tax resident
itsme or an eID card reader, to use MyMinfin
Your employer's assessment of whether the inbound taxpayer regime applies

Step-by-step

1
Establish whether you are a Belgian tax resident
Residence turns on where your home and centre of economic interests sit, with entry in the population register creating a rebuttable presumption. Residents are taxed on worldwide income; non-residents only on Belgian-source income, on a different return.
OnlineWho: You
2
Raise the inbound taxpayer regime at contract stage
Under BBIB the employer can pay part of your gross remuneration as tax-free expense reimbursement. The employer applies within a short window after employment begins, and if the window closes the regime is unavailable for that engagement. This is a conversation for the offer, not the first payslip.
Via employerWho: Your employerAt hiring
3
Know the brackets and where 50% begins
For income year 2026 the rates are 25%, 40%, 45% and 50%, with the top rate from roughly €48,000 of taxable income and a basic tax-free allowance around €11,180. Employee social security of 13.07% is deducted from gross before income tax is calculated, so budgeting from a gross figure overstates what arrives.
OnlineWho: You
4
Check the communal surcharge before you sign a lease anywhere on this coast
The additional communal tax is a percentage of the income tax you owe, voted by each municipality and published annually by FPS Finance. Bruges charges 6.9% for assessment year 2026; Knokke-Heist charges 0%, the only such rate in the country, and De Haan, Koksijde and several other coastal communes are also well below the national average. Your registered address on 1 January fixes the rate for that year.
OnlineWho: You
5
Understand what a second residence costs before you buy one
Bruges and its coastal neighbours levy an annual second-residence tax on property that is furnished and available but not the owner's registered main residence, and a separate tax applies to property let as tourist accommodation. If you buy a flat here and register your main residence elsewhere, you are in that category — and the planning rules on holiday lets in the centre mean you may not be able to let it out either. Check both before, not after.
OnlineWho: You
6
Check the pre-filled proposal rather than ignoring it
Many employees receive a proposed simplified return instead of a blank one. It still has to be checked and corrected — deductions the administration cannot see, such as childcare, pension savings, charitable gifts or a foreign account, will simply be missing. Accepting a wrong proposal by silence is on you.
OnlineWho: YouLate April to mid-July

Documents you’ll need

National register number and itsme or eID reader
Annual payslip summary (fiche 281.10)
Records of foreign accounts, insurance policies and property
Certificates for pension savings, childcare and mortgage deductions
Any inbound taxpayer regime confirmation

Things most newcomers don’t know

The only 0% commune in Belgium is twenty minutes from Bruges, and it is not a loophole.

The FPS Finance table for assessment year 2026 shows Knokke-Heist at 0.0% and Mesen at 9.0%, with Bruges at 6.9%. Coastal municipalities keep their surcharges low because a large second-home tax base carries the budget instead. That is a real difference on identical income — but it is decided by where you are actually registered on 1 January, and registration follows where you genuinely live. People do move for it; people also try to claim it without moving, and residence is exactly what the wijkagent verifies.

Source: FPS Finance — communal tax rates for assessment year 2026

The pre-2022 Belgian expat regime no longer exists, and its replacement was rewritten for 2025.

The special regime for foreign executives was abolished on 1 January 2022 and replaced by the inbound taxpayer regime (BBIB) and inbound researcher regime (BBIO). For remuneration from 1 January 2025 the tax-free expense allowance rose from 30% to 35% of gross, the €90,000 annual cap was abolished, and the minimum gross salary condition fell from €75,000 to €70,000, with researchers subject to no salary minimum. Social security did not follow, so the 30% and €90,000 limits still apply for contributions and payroll now diverges from tax. Almost everything written online describes either the abolished regime or the 2022–2024 version.

Source: FPS Finance; professional-firm circulars on the 2025 reform

A second residence here is taxed twice over, and the second charge is a planning rule rather than a tax.

The annual second-residence tax is the obvious cost. The less obvious one is that Bruges applies an absolute stop on new holiday lets inside the historic centre and admits them outside it only above 200 m² and up to eight people. So the investor's usual answer — buy it, let it to tourists, cover the tax — is closed off in exactly the part of the city people want to buy in. Anyone modelling a purchase on short-let income needs to read the planning position first.

Source: Stad Brugge; FPS Finance

The employer, not you, applies for the inbound regime, and there is no second attempt.

The regime is claimed by the employer within a defined period of the employment starting. Miss that window and it is unavailable for that engagement, permanently — which for a benefit running up to five years and worth as much as 35% of gross as tax-free reimbursement is an expensive oversight. Belgian HR teams that hire internationally know the deadline; a small West Flanders employer hiring its first foreign specialist may never have heard of it. Raise it explicitly during negotiation.

Source: FPS Finance

Common mistakes to avoid

Relying on anything written about the pre-2022 expat regime.
Letting the employer's window to apply for the inbound regime lapse.
Assuming a coastal commune's 0% surcharge can be claimed without genuinely living there.
Buying a flat in the centre on the assumption you can let it to visitors.
Accepting the pre-filled proposal without adding deductions the administration cannot see.

Some of this may be out of date. Spotted something inaccurate? Help us keep it right for the next newcomer.