World Most popular surnames by U.S. State April 13, 2017 Alex This post may contain affiliate links. As an Amazon Associate, we earn from qualifying purchases. Smith is the most common last name in the U.S. Reddit user: nodougbutdoug Related Posts:The Most Common Last Name In Every CountryHow Each State got its NameMost common surnames in the Italian RegionsThe most common surname in each UK provinceMap of common US surnamesEvery Country’s Favorite Children’s Toy, from Dolls…Map showing countries which since independence have…The Oldest Cities in the U.S. Mapped