Palazzo Costaguti, Renaissance palace in Jewish Quarter, Rome, Italy

Palazzo Costaguti is a Mannerist palace at the corner of Piazza Mattei and Via della Reginella in Rome's Sant'Angelo district. Its ochre facade rises from a rusticated grey stone base; the main entrance on Piazza Mattei has an architrave inscribed COSTAGUTI. The building extends along Via dei Falegnami, with rear facades on Piazza Costaguti.

The palace was built in the first half of the 16th century for Monsignor Constanzo Patrizi and later came under the ownership of the Costaguti brothers. These brothers served as treasurers for Pope Paul V and shaped the building's history.

The piano nobile keeps its original decoration, with frescoes by Guercino and Agostino Tassi in the Salone di Rinaldo e Armida, Taddeo and Federico Zuccari in the Sala dei Mesi, and Domenichino's Carro del Sole. The Costaguti coat of arms, three pointed lines with three stars, appears throughout the palace.

The palace is a private residence and the seat of Universitas Mercatorum, so the decorated piano nobile is not open to visitors. It stands at the corner of Piazza Mattei and Via della Reginella, with rear facades on Piazza Costaguti; the main entrance portal faces the Fontana delle Tartarughe. The Costaguti coat of arms, three pointed lines with three stars, appears throughout the restored 16th-century courtyard.

The Costaguti coat of arms, three pointed lines ending in three stars, appears throughout the palace, including the restored 16th-century inner courtyard. On the grand staircase, marble steps alternate between Carrara and peperino, and a marble bench still stands where those climbing the stairs once rested.