Peoria is a city in Maricopa and Yavapai counties in the State of Arizona. Most of the city is located in Maricopa County, while a tiny portion in the north is in Yavapai County. It is a major suburb of Phoenix. According to 2010 Census Bureau releases, the population of the city is 154,065. Peoria is currently the sixth largest city in Arizona for land area, and the ninth largest for population. It was named after Peoria, Illinois. The word "peoria" is a corruption of the Illini word for "prairie fire. It is the spring training home of the San Diego Padres and Seattle Mariners who share the Peoria Sports Complex.

Peoria's identity is more related to resort and leisure living than the past, as that type of lifestyle migrates from the northeast Valley to Peoria. Peoria's economic plan focuses on establishing the new Loop 303 freeway corridor as an industrial, commercial, mixed development use and less on traditional residential development. In July 2008 Money Magazine listed Peoria in the Top 100 Places to Live.