St Martin's Church dates from the 12th century and was entirely rebuilt in the 15th century. The North Chapel houses the tombs of the Cecil family, including monuments to William Cecil, the first Lord Burghley. The church was extensively restored in the 19th century. The war memorial inside has the name of Humphrey Nevinson from Lyndon who was in the Church Lads' Brigade associated with the church. In the detached part of the churchyard is the grave of Daniel Lambert, one of Stamford's most celebrated citizens.

Properly it is the Church of St Martin Without, Stamford Baron.