🇧🇪 COUNTRY A Belgium VS 🇨🇭 COUNTRY B Switzerland

Belgium produces a high total tax burden at €100,000 gross income by Western European standards, and the gap versus Switzerland is correspondingly large. Belgium's combined burden at €100,000 gross is approximately €46,977: IPP (income tax) of approximately €33,176 (federal tax of about €31,005 plus an assumed ~7% communal surcharge of about €2,170; municipalities set their own rate between 0% and 9%, e.g. Antwerp 7.0% and the City of Brussels 4.9% in the 2026 list, so the real figure depends on where you live) plus employee social security of €13,801 (ONSS €13,070 at 13.07% of gross, uncapped, plus a €731 special social security contribution). Switzerland Zurich (city) charges approximately €21,034 total (income tax ~€11,171 + AHV/ALV/BVG contributions ~€9,863, from the verified Zurich calculator; €100,000 is converted at about CHF 0.928 per EUR, ECB reference rate of 2 October 2026, i.e. CHF 92,790). Zurich saves approximately €25,943 — approximately €2,162 per month. Zug (an earlier estimate, not recomputed on the verified calculator, and on a different basis: income tax plus AHV/ALV without the BVG pension share that the Zurich figure includes, so the Zug saving is somewhat overstated) saves approximately €35,257 — approximately €2,938 per month. Belgium's ONSS at 13.07% with no upper cap is the defining differentiator versus Switzerland. At €200,000, Belgium's ONSS alone is €26,140. Switzerland's AHV/IV/EO (5.3%) has no earnings ceiling at all — it applies to 100% of gross salary; only ALV's 1.1% stops, at CHF 148,200. At typical incomes (around CHF 100K), Swiss employee SS (AHV/IV/EO plus ALV) works out to approximately CHF 6,400/year (about CHF 9,600 with the statutory-minimum BVG pension share), and the AHV/IV/EO part keeps rising in line with income. The uncapped nature of Belgium's ONSS means it functions as a second income tax layered on top of the already-high IPP rates. Belgium's special inbound (impatriate) tax regime provides relief for qualifying internationally mobile professionals: up to 35% of remuneration can be paid as a tax-free reimbursement of employer-specific costs, with no annual cap (Law of 18 December 2025, applying from 1 January 2025; before that the allowance was 30% capped at €90,000), for up to 5 years (extendable by 3 years under conditions, per FPS Finance circular 2026/C/51); how the extra 5 percentage points are treated for social-security contributions should be checked with the ONSS/RSZ. Our calculator does not model this regime, so no Belgian figure with the regime is shown; on a rough estimate the Belgian total at €100,000 would still be above Zurich's €21,034. Switzerland's 0% CGT for private investors on movable assets such as shares contrasts with Belgium, which since 1 January 2026 taxes private investors' gains from financial assets at a flat 10% (the first €4,855 of gains each year is exempt; 30% withholding on dividends is unchanged), and a 0.35% stock exchange tax (maximum €1,600 per transaction) applies on share trades. Belgium provides universal healthcare through RIZIV/INAMI (mandatory health insurance via mutuality), low-cost university education, and extensive social protections largely funded by social contributions and taxes. Switzerland's mandatory private Krankenkasse reduces the headline Swiss tax advantage by roughly CHF 3,000–8,000+/year per adult (the 2026 national average adult premium is about CHF 465 a month). Zurich figures are for a single filer with no children and no church tax and come from our verified City of Zurich calculator; they count the employee's minimum BVG pension contribution as a cost.