The vocabulary
Steuerfuss (literally "tax foot"). The multiplier each Swiss commune applies to the cantonal simple tax to compute its share of your tax bill. Bilingual aliases:
- French: coefficient d'impôt communal
- Italian: moltiplicatore d'imposta comunale
- French (GE/VD-style): centimes additionnels — slightly different (it's added on top of base, not a replacement)
The mechanic
Your taxable income enters the cantonal simple-tax scale (one per canton, published in the StG / LF). The scale produces a number in CHF. That's the einfache Steuer. It is not what you pay — it is the unit that gets multiplied.
Three multiplications happen:
- Cantonal multiplier (Staatssteuerfuss): the canton's share. E.g. ZH 99 %, BE 306 %, ZG 80 %.
- Commune multiplier (Gemeindesteuerfuss): the commune's share. This is the number you see on Optiqo.
- Church tax (optional, only if you're a registered member).
Total cantonal+communal tax = einfache_Steuer × (canton_mult + commune_mult) ÷ 100.
Why the numbers look so different across cantons
A Steuerfuss of 50 % in Zug is not directly comparable to a 100 % in Vaud, because the underlying simple tax in those cantons is computed by completely different scales. Some cantons have steep early brackets and a low top; others have flat early brackets and a tall top. The Steuerfuss is just a final multiplier on whatever the canton's curve produced.
So when Optiqo shows you "Zug 50 %, Bern 154 %", the right interpretation is:
- Within the same canton, 50 % vs 60 % means the second commune costs 20 % more.
- Across cantons, you cannot compare Steuerfuss directly. Compute the actual tax burden at your income — that's what Optiqo's income-aware atlas does.
Special cases
- Geneva (GE) uses centimes additionnels — an additive rather than replacement multiplier. The Genève commune adds 45.49 centimes on top of the 47.5 cantonal centimes. Plus a 12 % rebate. Optiqo handles this special-case math.
- Basel-Stadt (BS) doesn't have a commune multiplier for Basel city — the canton taxes Basel residents directly. Only Riehen and Bettingen are separate communes with their own multiplier.
- Glarus (GL) has just 3 communes after the 2011 mass merger. The variance is small.
- Jura (JU) publishes its commune multipliers asquotité d'impôt in decimal (e.g. 1.95) rather than percent (195 %). Same mechanic, different unit.
- UR, OW publish in Einheiten (units) where 1 Einheit = 100 %. Optiqo normalises to percent for comparability.
When commune Steuerfuss changes
Commune budgets are voted in November-December for the following year. Most communes change Steuerfuss only after a strategic budget review (every 3-5 years) but small adjustments are common. Big headlines for 2026: Canton Zürich cut its cantonal Steuerfuss from 98 % to 95 % — biggest cut in 20 years.