Fincham is a village in the King's Lynn and West Norfolk district, ten miles S of King's Lynn. The church stands in the village centre, and is an imposing mid-15thc building of flint and carstone with ashlar dressings, consisting of a 5-bay aisled nave with a S porch, a chancel and a 3-stage W tower. The only Romanesque feature is an early-12thc font, brought to St Martin's from the former church of St Michael, Fincham, a 12th and 13thc church demolished in the mid-18thc.

The Domesday Survey records that Fincham was a large settlement, and 6 tenants-in-chief are listed. They were William of Warenne, Hermer of Ferrers, Reginald son of Ivo, Ralph Baynard, and the abbeys of Bury St Edmunds and Ely. Both St Martin's and St Michaels are described at length in Blomefield and Parkin (1807), 354-64, from which it is clear that St Michael's, the original home of the font, was standng and roofed with lead when Parkin saw it. Although the volume was not published until 1807, Blomefield had died in 1752 and Parkin in 1765.

A repair runs around all four faces of the basin near its lower edge. Bond refers to the colonnettes as 'modern'.