The church comprises a 12thc. nave, extended westward in the 13thc., and a 13thc. chancel and S aisle; the 13thc. W tower is formed in the angle of the nave and S aisle. There is extensive use of grey lias rubble work, also some shell bearing limestone and red sandstone. The N and S doorways are Romanesque, as is the chancel and sculpture in the nave E wall.

There is no mention of Halford in the Domesday Survey, but it seems that Kenilworth Priory has some rights - in 1247 the Bishop of Worcester obtained the right of advowson, with the consent of Kenilworth, in return for a pension. The church continued with Worcester until 1919 when it was transferred to the new diocese of Coventry.

The figural capital on the N doorway is similar to the very eroded example on the N doorway of St Peter's church, Whatcote, less than 5km away. The niche on the R of the chancel arch is in its original position as the colonette is carved from the two blocks adjacent to it. The feature on the other side of the chancel arch to the niche is the remnants of another niche. Pevsner describes the angel as the best piece of Norman sculpture in the county. The Romanesque sculpture of Halford has been closely studied by Kahn, who has commented that the sculptor of the angel was probably aware of Anglo-Saxon manuscripts, and that there is a similarity to a carved angel at Worcester cathedral, although the latter is not necessarily by the same sculptor. The present inscription (from Luke 1:28) on the angel's scroll is modern. Kahn also suggests that the L niche is in situ because the colonette is carved from the two blocks which flank it. She prefers the interpretation of the figures that once flanked the chancel arch as forming an Annunciation, while Pevsner and Wedgwood suggest that they were related to a rood above the arch, in which case the surviving S figure would represent St John the Evangelist.

The dedication is recorded as 'Our Blessed Lady' in Crockford's Clerical Directory.