The Americas Zone was one of three zones of regional competition in the 2018 Fed Cup.
The seven teams were divided into two pools of three and four teams.
The two pool winners took part in a play-off to determine the nation advancing to the World Group II play-offs.
The two nations finishing last and second last in their pools took part in relegation play-offs, with the two losing nations being relegated to Group II for 2019.
Puerto Rico withdrew before the tournament due to the economic circumstances caused by Hurricane Maria.