Paris has operated rent control (encadrement des loyers) since 2019: a local rent observatory publishes a reference rent per m² for each neighborhood, building age, and room count, and landlords cannot charge more than 20% above that reference except via a rarely-valid documented 'complément de loyer' premium. This experimental mechanism was extended by three years under Article 85 of the 2022 '3DS law' and is set to expire on 23 November 2026, with permanent adoption still pending as of 2026. Studies show rent control has moderated Paris rent increases by an average of -5.2%, with the effect strengthening over time (-2.5% in 2019-2020, -5.9% in 2022-2023, -8.2% in 2023-2024).