The members of the New Jersey Legislature are chosen from 40 electoral districts.

In New Jersey, each district elects one Senator and two Assembly members.

(States that have similar practices are Arizona, Idaho, Maryland, North Dakota, South Dakota, and Washington.)

Districts are reapportioned decennially by the New Jersey Apportionment Commission following each United States census, as provided by Article IV, Section III of the state Constitution.

The most recent changes to the legislative districts were in effect in the primary elections held in June 2011 and the general elections of November 2011, following the 2010 United States census.