Zurich Takes a Harder Line on Duplicate Property Listings Than Most European Rivals

The Zurich cantonal housing office confirmed this spring that duplicate image listings — identical apartment photos posted multiple times across platforms such as Homegate, ImmoScout24 and Comparis — now account for a measurable share of the advertised rental stock in the city, inflating the apparent supply in a market where the vacancy rate sat at just 0.07 percent as of the most recent city statistical survey. That near-zero figure makes every phantom listing count.

The timing matters. Zurich's Wohnungsnot — the housing shortage that has pushed average monthly rents for new-let three-room apartments in districts like Kreis 4 and Kreis 6 above 2,800 francs — has made the search process gruelling for ordinary renters. When the same flat appears four times under four different agency names, it distorts how tight the market truly looks and can cause applicants to submit multiple deposits simultaneously, sometimes losing non-refundable fees on listings that were never genuinely separate offers.

What Zurich Is Actually Doing

The city's response has taken two tracks. Homegate, which is headquartered in Schlieren and handles a large share of Swiss residential listings, began rolling out perceptual hash matching — a technique that flags visually near-identical images regardless of file compression or minor cropping — in the second half of 2025. The system was developed partly in collaboration with researchers at ETH Zurich's Computer Vision Lab, which has published peer-reviewed work on large-scale image deduplication. Under the programme, flagged listings are placed in a review queue before going live rather than being pulled automatically, a design choice that reflects Swiss legal caution around property rights and data privacy.

The cantonal building directorate, the Amt für Raumentwicklung, has also been consulting with platform operators since late 2024 about voluntary compliance standards for listing provenance — meaning agencies must now log the original source of each photograph submitted. That is a more systematic requirement than anything currently in place in Berlin, where the GdW landlord federation has discussed similar measures but not yet agreed a binding framework, or in Vienna, where the Wiener Wohnen social housing authority operates its own listings system in a largely siloed way that does not interact with private portals.

How the Competition Compares

Amsterdam moved earlier than most. The municipality partnered with Funda, the dominant Dutch listings portal, in early 2024 to require geo-tagged photography with verifiable timestamp metadata, effectively making it technically difficult to repost images from a previous tenancy cycle as if they represented a currently available unit. The Dutch approach is considered more prescriptive; it has reduced flagged duplicate image incidents on Funda by a figure the platform has publicly described as significant, though the exact percentage has not been independently audited.

London's situation is more fragmented. Rightmove and Zoopla operate under voluntary codes overseen by the Property Ombudsman, but enforcement is complaint-driven rather than algorithmic. A 2025 review by the National Trading Standards Estate and Letting Agency Team found that misleading listing imagery remained among the top five complaint categories — but the review did not produce mandatory platform-level deduplication requirements.

Zurich's edge, according to housing researchers familiar with the Swiss market, stems partly from the direct-democracy pressure that tenants' associations such as the Mieterinnen- und Mieterverband Zürich can apply at cantonal level. That organisation has been pushing publicly since 2023 for stricter listing hygiene as a component of broader rental market transparency. It does not have the power to compel platforms, but its political weight in a city where renters make up roughly 90 percent of households is considerable.

For anyone currently searching for a flat in Zurich, the practical upshot is modest but real. Cross-checking listings manually across Homegate, ImmoScout24 and the city's own Liegenschaftenverwaltung portal for municipal flats remains advisable. Reverse image search tools are free and take under a minute per listing. If the same photograph appears under different agency names at different prices, the safer course is to contact the building management directly and confirm the listing reference number before paying any reservation fee — a step that consumer protection body Konsumentenschutz has recommended in its guidance for the 2025–26 rental season.