The City of Boston is the capital and most populous metropolis of Massachusetts in the United States, as well as the country's 24th-most populated city. Boston is formally known as the City of Boston, and it is the state capital. The city proper has a surface area of 48.4 square miles (125 km2) and will have a population of 675,647 people in 2020, making it the most populated city in New England and the largest in the United States. It is the county seat of Suffolk County (although the county government was disbanded on July 1, 1999). The city serves as the economic and cultural hub of a much larger metropolitan region known as Greater Boston, which had a population of 4.8 million people in 2016, according to census estimates, and was the tenth-largest metropolitan statistical area (MSA) in the nation. Greater Providence, Rhode Island, including the surrounding combined statistical area (CSA), which usually corresponds to the commuting region and includes Providence, Rhode Island, is home to about 8.2 million people, making it the sixth largest populated city in the United States.
Today, Boston is a flourishing hub for scientific research of international repute. The number of schools and institutions in the Boston region makes it a world leader in higher education, particularly in the fields of law, medicine, engineering, and business. The city is also regarded as a worldwide leader in innovation and entrepreneurship, with over 5,000 companies in the area. Other sectors of Boston's economy include banking and professional and commercial services; biotechnology; information technology; and government-related industries. Residents of the city have the highest average rate of philanthropy in the United States, and the city's companies and institutions have consistently ranked as among the nation's best in terms of environmental sustainability and investment. As a result of gentrification, the city has one of the highest expenses of living in the United States, despite the fact that it continues to score well in global livability rankings.