The Northampton and Rutland Militia was a militia regiment in the United Kingdom from 1860 to 1881, when it was transferred into the Northamptonshire Regiment.
The regiment was formed in 1860 by the amalgamation of the Northampton Militia and the Rutland Militia, and was ranked as the 48th regiment of militia. In 1874 the regiment was split into two battalions, and in 1881, under the Childers Reforms, these were transferred into The Northamptonshire Regiment as the 3rd and 4th Battalions.
In 1899 these were amalgamated into a single battalion, the 3rd, which was embodied during the South African War in 1900. It was disembodied at the end of that year, but re-embodied in 1902, when it served in South Africa.
During the Haldane Reforms in 1908 the battalion was transferred to the Special Reserve, and was embodied on mobilisation in 1914 for the First World War. As with all Special Reserve battalions, it served as a regimental depot, and was disembodied following the end of hostilities in 1919. The battalion nominally remained in existence throughout the Second World War, but was never activated, and was finally disbanded in 1953.