Massachusetts House of Representatives' 4th Essex district in the United States is one of 160 legislative districts included in the lower house of the Massachusetts General Court. It covers part of Essex County. Democrat Estela Reyes has represented the district since 2023.

Massachusetts Senate's 1st Essex and Middlesex district in the United States is one of 40 legislative districts of the Massachusetts Senate. It covers 17.8% of Essex County and 2.5% of Middlesex County population. Republican Bruce Tarr of Gloucester has represented the district since 1995.