North Township is one of 11 townships in Lake County, Indiana. As of the 2020 census, its population was 156,686.
North Township was formed in 1837 as one of the original townships of Lake County. At that time it stretched across the entire north portion of the county. Its boundaries were reduced a number of times in the 19th century, including in 1849 by the formation of Hobart Township south of the Little Calumet River and in 1883 by the formation of Calumet Township, Lake County, Indiana from the area between Hobart Township and Lake Michigan. In 2022, its boundaries expanded to include much of Griffith, which moved from Calumet Township to North Township after a lengthy dispute between Griffith and Calumet Township.
The earliest known community in North Township was Gibson, now part of Hammond, which was located near the site of the present-day Gibson Yard on the Indiana Harbor Belt railroad.
According to the 2010 census, the township has a total area of , of which (or 90.32%) is land and (or 9.68%) is water.
The five municipalities that lie totally within the boundaries of North Township, and their populations as of the 2010 Census, are:
In addition, the town of Griffith (population 16,893) lies primarily in North Township, although portions of it are also in St. John Township.
There are five public school districts in North Township:
The privately owned and operated Bishop Noll Institute is located in Hammond.