In short: In cantonal votes in the 2020s, the city of Zurich deviates 10 percentage points from the canton-wide result. In the 1970s, it was 3.

Does the city of Zurich also deviate from its own canton? In an earlier note, the city’s growing deviation from the national result was documented. Here, the same measurement at the cantonal level.

Context
In cantonal votes, all eligible voters in the Canton of Zurich decide on the same ballot — laws, budgets, constitutional amendments. The city of Zurich is one of 162 municipalities in the canton. Its result can be directly compared to the canton-wide outcome.

For every cantonal vote since 1933, the difference between the city of Zurich’s result and the canton’s can be calculated — regardless of direction.1

Median Deviation: City of Zurich vs. Canton of Zurich
Cantonal votes, median absolute difference in percentage points per decade.
1970s
2.9 PP (138 votes)
1980s
3.6 (136)
1990s
3.4 (152)
2000s
5.6 (74)
2010s
8.2 (98)
2020s
10.0 (43)
Absolute difference |ZH − Ct. ZH| in percentage points, median per decade. Source: Open Data City of Zurich.

In the 2020s, the city of Zurich deviates 10.0 percentage points from the canton-wide result in a typical vote. In the 1970s, it was 2.9. The deviation has more than tripled.2

Until the 1990s, the deviation stayed in a narrow band of 2.9 to 3.6 percentage points. From the 2000s onward, it rises sharply — from 3.4 to 5.6, then 8.2, then 10.0. The increase is steeper than for federal votes, where the deviation roughly doubled over the same period.

The five largest deviations since 2000:

BallotCity of ZurichCantonDifference
Affordable Housing (Nov. 2025)59.7 %40.7 %+19.0 PP
Scholarship Act (Sep. 2024)64.6 %45.6 %+19.0 PP
Parental Leave Initiative (May 2022)52.9 %35.2 %+17.7 PP
Energy Act / Climate (Sep. 2025)58.0 %40.5 %+17.5 PP
Affordable Housing / Tiebreaker (Nov. 2025)57.7 %40.6 %+17.1 PP

The numbers show the size of the deviation between the city and the canton it belongs to. What drives it cannot be determined from this measurement alone.

Open Questions
The increase from the 2000s onward is notably abrupt. Only 43 cantonal votes are available for the 2020s so far. The measurement shows the distance, not the cause.

  1. The measure used is the absolute difference between the yes-vote share of the city of Zurich and that of the Canton of Zurich, regardless of direction: |yes% city ZH − yes% canton ZH|. Summarised as the median per decade. The median captures the typical deviation and is robust against individual outliers. ↩︎

  2. Open Data City of Zurich — Vote Results since 1933. Own analysis: 987 cantonal votes since 1933, of which 641 since 1970. All values calculated from city-wide results. ↩︎