The church is Grade II* listed by the Department for Digital, Culture, Media and Sport.

The only remaining Romanesque work is the former south transept arch of the tower, which was moved to the north side during the 19th-century restoration.

There is also a chapel dedicated to the memory of Archbishop Thomas Cranmer, who was born and raised in Aslockton, which was a chapelry of Whatton at that time.

The two corbel heads in the chapel date from about 1300 and depict King David and an angel.

[3] Apart from interesting architectural detail (the lower part of a now redundant newel staircase, the Decorated recess containing a statue of a former incumbent [1304–10], and a double piscina), there is a late 14th-century effigy of a Knight Templar in armour and another of a cross-legged knight of the early 14th century, and a tablet in memory of Thomas Cranmer, father of the archbishop, who was born in Aslockton in 1489.