Beachamwell St. Mary is a Grade I listed building, and one of 124 existing round-tower churches in Norfolk. It is built from flint, mainly rendered with ashlar and with some brick dressings. It has both thatch and lead roofs. St Mary is the last surviving church of four that once served this area. The round tower is one of the earliest in Norfolk, being early 11th century.
There is a pair of wall tablets in the chancel to John Motteux (died 1793) and John Motteux (died 1843) set beneath the crocketted ogee arches with carved head stops and fleurons.