Johan Magnus Halvorsen (10 June 1853 – 14 February 1922) was a Norwegian politician for the Free-minded Liberal Party.

[1][2] Halvorsen was born at Ålesund in Møre og Romsdal, Norway.

He started his business career as a sales representative in Vanylven Municipality in Sunnmøre.

[3] Halvorsen was a member of the city council of Trondheim 1895-1904 and again from 1910.

This article about a Norwegian politician born in the 1850s is a stub.