Portland is a city in the U.S. state of Maine. It is the most populous city in the state and the seat of Cumberland County. Portland's population was 68,408 in April 2020. The Greater Portland metropolitan area has a population of approximately 550,000 people. Historically tied to commercial shipping, the marine economy, and light industry, Portland's economy in the 21st century relies mostly on the service sector. The Port of Portland is the second-largest tonnage seaport in the New England area as of 2019.