Illegal graffiti refers to the unauthorized marking of public or private property and is commonly treated as vandalism, often subject to fines or other penalties. Graffiti becomes illegal when it is created without the owner’s permission, whereas works produced with consent—such as approved murals or street art—are considered legal. The key distinction therefore lies in the authorization of the property owner. Unsightly or unwanted graffiti should be removed as quickly as possible to prevent further damage or copycat defacement. At the same time, the canton of Basel-Stadt actively supports the creation of street-art murals by providing designated walls and encouraging artistic expression in appropriate locations.

In August 2026, a total of 68 graffiti removals were recorded in the Canton of Basel-Stadt. Of these, 67 removals concerned private buildings (SprayOut), while only 1 removal involved public facilities (SprayEx). Compared to the average monthly graffiti removals of 144.7 recorded since November 2023, this number is considered to be high.

The top five communities with the highest number of graffiti removals were Am Ring (9), Matthäus (8), St. Johann (7), St. Alban (7), and Gotthelf (6). The bottom five communities, where the least removals were required, were Gundeldingen (1), Bruderholz (1), Vorstädte (2), Rosental (2), and Breite (3).

The monthly time series shows a clear structural break in the data. Before October 2023, monthly removals typically ranged between roughly 28 and 91, with occasional peaks such as 91 in January 2019 and June 2021. From November 2023 onward, the numbers jumped sharply, reaching 200 in November 2023 and remaining mostly between 100 and 178 thereafter. This increase is explained by the fact that reporting of graffiti removals on private buildings (SprayOut) only started in October 2023. Before that date, the series mainly captured removals on public facilities, so the post-October 2023 figures reflect a broader scope of reporting rather than a sudden surge in vandalism. Within the more recent period, August 2026 stands out as a relatively low month with 68 removals, following a peak of 212 in March 2026 and 208 in April 2026, and a decline through May, June, and July.

The Canton of Basel-Stadt maintains cleanliness in public spaces through rapid response and financial support. Illegal graffiti on public infrastructure is typically removed within 48 hours of being reported, which helps prevent further vandalism. Residents can report graffiti through the cleanliness hotline or by completing the online form. The canton also financially supports private property owners in removing graffiti, covering a substantial portion of cleaning costs. In addition, Basel actively promotes legal street art by providing advisory services, supporting property owners who wish to commission murals, designating walls for legal painting, and encouraging high-quality street art as a way to beautify the city and reduce vandalism.