What is the postal code of Solothurn?

The postal code of Solothurn is 4500.

What is the tax rate in Solothurn?

The municipal tax multiplier of Solothurn is 112% (2026); canton SO levies 104%.

How many residents does Solothurn have?

Solothurn has 16'855 residents.

How many foreign residents live in Solothurn?

Solothurn has 3'793 foreign residents, a share of 22.51% (2024).

Which party is strongest in Solothurn?

In the 2023 National Council election, SP was the strongest party in Solothurn with 27.331% of the vote.

Switzerland · Canton SO

Solothurn

4500

SO CANTON4500

Residents

16'855

Area

6.3 km²

Elevation

435 m a.s.l.

Tax multiplier

112%

Postal codes

Recent federal votes

BFS · sd-t-17-02

14.06.2026Änderung des Bundesgesetzes über den zivilen Ersatzdienst (Zivildienstgesetz, ZDG)● Switzerland: accepted · turnout 61.8%41.2% yes

14.06.2026Volksinitiative «Keine 10-Millionen-Schweiz! (Nachhaltigkeitsinitiative)»● Switzerland: rejected · turnout 62.2%27.8% yes

08.03.2026Bundesgesetz über die Individualbesteuerung● Switzerland: accepted · turnout 58.4%67.2% yes

08.03.2026Volksinitiative «Für eine gerechte Energie- und Klimapolitik: Investieren für Wohlstand, Arbeit und Umwelt (Klimafonds-Initiative)»● Switzerland: rejected · turnout 58.7%40.5% yes

Source: BFS · retrieved 20.07.2026

Politics

National Council election 2023

SP27.3% · strongest party

SP27.3%

FDP19.8%

GRÜNE17.9%

SVP12.4%

Mitte10.6%

Source: BFS · retrieved 20.07.2026

Taxes 2026

ESTV

Municipal tax multiplier112%

Cantonal tax multiplier104%

112%CH range 25%525%

Tax rank 26 of 104 in canton Solothurn

Source: ESTV · retrieved 20.07.2026

Climate

Grenchen · 9.5 km

Annual mean temperature 202510.5 °C

Precipitation 20251'101 mm

10.5 °CCH range -5.5°14°

Source: MeteoSwiss · retrieved 24.07.2026

Municipality

Wikidata · CC0

Head of governmentKurt Fluri · FDP.Die Liberalen

Websitestadt-solothurn.ch ↗

Source: Wikidata · retrieved 27.07.2026

Postal codes (1)

swisstopo

4500

Solothurn

Localities

swisstopo · 1

Solothurn4500

Nearby municipalities

swisstopo

Feldbrunnen-St. Niklaus

SO · 2.1 km

Bellach

SO · 2.1 km

Frequently asked questions

What is the postal code of Solothurn?: The postal code of Solothurn is 4500.
What is the tax rate in Solothurn?: The municipal tax multiplier of Solothurn is 112% (2026); canton SO levies 104%.
How many residents does Solothurn have?: Solothurn has 16'855 residents.
How many foreign residents live in Solothurn?: Solothurn has 3'793 foreign residents, a share of 22.51% (2024).
Which party is strongest in Solothurn?: In the 2023 National Council election, SP was the strongest party in Solothurn with 27.331% of the vote.

Map

OpenStreetMap