This dataset supports the analysis presented in "Milan as a 15-minute city: the relationship between prices and amenities." It contains three files: Original_Database.xlsx — Raw open-source data on urban amenities in the Municipality of Milan (street registry, OMI real estate zones, supermarkets, healthcare facilities, public and private schools, green areas, metro stations). Sources include Comune di Milano, Agenzia delle Entrate, Regione Lombardia, and AMAT. Coordinate system: WGS84. Compiled March 2025. Amenity_OMI_Spatial_Join.xlsx — Each amenity type spatially joined to OMI real estate zones via QGIS. Includes aggregated counts and densities per OMI zone used as explanatory variables in the first hedonic price regression (density approach). Cumulative-service_approach.xlsx — Main steps of the construction of a cumulative accessibility index based on the 15-minute city framework. It includes Haversine distances between street midpoints and each amenity, and the final aggregated dataset at OMI-zone level used in the second regression (cumulative-service approach).