Many of the rooms in the palace were redecorated starting in 1846, a commissions entrusted to Luigi Scrosati and Giuseppe Bertini.

The architect Simone Cantoni (1736–1818) rebuilt the palazzo in its present Neoclassical style with an English-style interior garden.

In 1850–1853, Poldi Pezzoli commissioned the architect Giuseppe Balzaretto to refurbish his apartment.

During World War II, the palazzo suffered severe damage, but the artworks had been placed in safe storage.

Works on display include Italian painters such as: Painters in the collection include: Breughel the younger; Cranach; Goltzius; James Baker Pyne; Thomas Shotter Boys; Sutterman; Teniers the younger; Jacob Toorenvliet; Pierre Tetar van Elven; Mathijs Van Hellemont; Jan Van der Meer II; Willem Van Mieris; Jacob Ferdinand Voet; Nicolaus Alexander Mair Von Landshut, (Mair Landshut); and Cornelis de Wael.