The Manchester B&M Switch Tower, also known as the MA Tower is a historic and abandoned building in Manchester, New Hampshire. This one-story brick structure was built in 1944 to replace two traditional wood towers. It stood alongside the Manchester and Lawrence Branch (M&L) and operated 24/7. The train directors stationed at the tower regulate the railroad using a “Manchester-Type” control machine, the first of its type, which was fabricated and installed by Union Switch and Signal Company.

MA Tower was responsible for the double-track New Hampshire main line from a point that began just south of West Mitchell Street crossing, went through the Manchester yards, and then up to a point north of the city. Additionally, it controlled all switches and signals to and from the three branches which terminated in Manchester, New Hampshire. These included the Manchester and Lawrence Branch, the Portsmouth Branch, and the Goffstown Branch. Eventually, the signal control machine from the MA Tower was transferred to North Billerica, Massachusetts. Then the tower was closed down and abandoned. It is privately owned by the Boston and Maine Corporation and stores some random equipment.