This was built in Church Lane from the materials of the original St. Mary's church, demolished in 1784 by Thomas Assheton Smith II. It was built as a burial chapel and used by the Assheton Smiths as a family chapel. It was also the only church for South Tidworth until 1880 and it also became the parish church. It is very small, only 22 feet long by 18 feet wide, and has a west porch with a belfry above it. There is a window of 14th century design in the east wall. Memorials were removed from the old church and reset here and new ones were added. There is an 18th century font in veined marble. The chapel was superceded as the parish church in 1880 when the new church of St. Mary opened, but is still maintained.