January 2017

Download this layer (.zip file, 1.6 MB):
 - ESRI Shapefiles (arc and polygon)
 - ArcMap layer files (.lyr) (for ArcMap 10 and 9.0*)
* The data sources in the LYR for Arc 9 will need to be reset)

Search a database to find your LegislatorsView and search a map to find your Legislators


The Massachusetts Senate Legislative Districts datalayer reflects the state Senate district boundaries as defined by Massachusetts General Laws, Chapter 57: Section 3. These 40 districts are those used in the Fall 2012 elections and beyond, until they are redrawn using the 2020 decennial Census. The names of the statewide datalayers are SENATE2012_POLY (polygons) and SENATE2012_ARC (arcs). These replace the older SENATE02_ARC and SENATE02_POLY layers.

View and query these data in the Legislative District Viewer. Users may search for their district based on municipality, legislator, or district name. When identifying the districts, the results contain links to their senator's Web pages.


Staff at the Massachusetts Senate developed this layer with its contractor, Caliper Corp. (Newton, MA), using Maptitude for Redistricting software. MassGIS appended the 1:100,000 coastline and state outline and added the senators' name and party attributes.


The SENATE2012_POLY attribute table has the following fields:
SENDISTNUM 5 / I Senate District number
SEN_DIST 43 / C Name of Senate District
SEN_FIRST 13 / C First name of Senator
SEN_LAST 15 / C Last name of Senator
SEN_PARTY 3 / C Senator's political party
SENATOR 40 / C Senator's full name and party
URL 150 / C Senator's Web site address

In the SENATE2012_ARC attribute table, the field OUTLINE is coded as follows:

  • 0  =  Internal district boundaries
  • 1  =  State
  • 2  =  Coastline


MassGIS maintains the layer and will make updates as needed. The January 2017 update includes all polygon attribute changes from the fall 2016 elections.

Also see the state House and Congress data layers.

Last Updated 1/4/2017