Fontalba Palace, Government building in Almagro district, Madrid, Spain

Fontalba Palace is a rectangular palace at Calle Fortuny 4 in Madrid's Almagro district, built on a plot of the former Loinaz orchard. It has 985 square metres over three floors plus a semi-basement, organised around a large covered hall or courtyard with a glazed roof on the main floor. Since 1991 it has housed the Fiscalía General del Estado.

Architect José María Mendoza Ussía designed this residence in 1911 for Francisco de Cubas y Erice, the second Marquis of Fontalba. The building was eventually converted to serve government purposes rather than as a private home.

The palace shows how wealthy Madrid families lived and entertained in the early 1900s, with spaces designed for formal gatherings and social events. The interior layout with a central courtyard reflects the period's preference for elegant, inward-facing living spaces.

The palace stands at Calle Fortuny 4, in the Almagro neighbourhood of the Chamberí district, with the entrance on Fortuny itself. Since 1991 it has housed the Fiscalía General del Estado, so the interior is a working office and visits are not generally open; the 1911 façade and the glazed courtyard are best appreciated from outside. In September 2024 the state bought the adjoining building at Castellana 19 to bring all the prosecutor's office services together.

The palace was built on a plot of the former Loinaz orchard, and its 985 square metres are arranged over three floors plus a semi-basement around the great covered hall. Since 1991 it has housed the Fiscalía General del Estado; in September 2024 the state bought the adjoining building at Castellana 19 for 67.4 million euros to bring all its services together.