Atlantic Beach is a city in Duval County, Florida, United States and the second largest of the Jacksonville Beaches communities. When the majority of communities in Duval County consolidated with Jacksonville in 1968, Atlantic Beach, along with Jacksonville Beach, Neptune Beach, and Baldwin, remained quasi-independent. Like the other towns, it maintains its own municipal government, but its residents vote in the Jacksonville mayoral election and have representation on the Jacksonville city council. The population was 13,513 at the 2020 census, up from 12,655 at the 2010 census. It is part of the Jacksonville, Florida Metropolitan Statistical Area.