Frost line depth in Worcester County, MA
How deep the ground freezes in Worcester County, MA
31 in. Dig to 32 in, just below the frost. Nearest NOAA station: Worcester Rgnl Ap, 4.5 mi.
Your building department sets the legal frost line depth (IRC Table R301.2(1)); footings must go below it (R403.1.4.1). Call them before you dig.