West Springfield is a city in Hampden County, Massachusetts, United States. It is part of the Springfield, Massachusetts Metropolitan Statis…West Springfield is a city in Hampden County, Massachusetts, United States. It is part of the Springfield, Massachusetts Metropolitan Statistical Area. The population was 28,835 at the 2020 United States Census. The city is also known as "West Side", in reference to the fact that it is on the western side of the Connecticut River from Springfield, a fact which played a major part in the town's early history.