The following towns define Essex County and the Merrimack Valley Region

 Amesbury
Andover
Beverly 
Billerica
Boxford
Bradford           
Byfield
Chelmsford
Danvers
Dracut
Dunstable
East Lynn
Essex, MA
Georgetown
Gloucester
Groveland
Hamilton
Hathorne
Haverhill
Ipswich
Lawrence
Lynn
Lynnfield
Lowell
Manchester
Marblehead
Merrimac
Methuen
Middleton
Nahant
Newbury
Newburyport
North Andover
Peabody
Pepperell
Prides Crossing
Rockport
Rowley
Salem
Salisbury
Salisbury Beach
Saugus
South Hamilton
Swampscott
Tewksbury
Topsfield
Tyngsborough
Ward Hill
Wenham
West Boxford
West Lynn
West Newbury
Westford