The authors agree in noting the Lombard origin of the surname. E. Rossoni specifies that it is typical of the Milan area, with a documented presence in localities such as Monza, Pogliano Milanese, Cerro Maggiore, Brugherio, Rho, Besana in Brianza, Muggiò, Lainate, Lissone, Seregno, Biassono, Villasanta and Cologno Monzese. According to Rossoni, the origin would be toponymic, possibly linked to localities called Pagliaro, in the Bergamo area, or Pagliaro Superiore, in the Alessandria area. Traces of the surname are documented from the year 1400.

R. Brondolo broadens the geographical distribution by noting that the surname also migrated towards southern Piedmont, and proposes a different etymology: it would derive from the Latin paleata domus, an expression that means "house with a straw roof". The variant Paliari, of practically isolated presence, would according to Rossoni be a modification of the main surname.