Coates is a small settlement about 2.5 miles NNW of Kemble. The church lies to the W of the village and has a chancel, a nave, a S aisle with a porch, and W tower; there are two projecting chapels on the N side, one on the chancel and one on the nave. The church is approached from the N.

Surviving Romanesque sculpure are a 12th-c S doorway, a reset chancel arch and a font.

At DB, there were six manors in the Coates area each with its separate Norman lord. The largest of the three in ‘Achelie’ or Oakland – and the manor with a priest – had been granted to Walter de Laci (died 1085). The manor was held thereafter by his sons Roger and then Hugh de Laci (died 1121, the founder of Llanthony priory). The rest of the complex history of these manors is set out in Thorp 1928. The dedication to St Matthew is 'ancient' according to Arnold-Forster (1899).

The S arcade has water-holding bases, moulded capitals and double-chamfered pointed arches so it was not recorded; the S doorway has earlier features, so presumably it had been re-used when the S arcade and aisle were built. Usually the first aisle built is on the N side where there are few burials, but here the aisle advanced over the populated part of the graveyard, which might account for the doorway being set on grave slabs.

The chancel arch was ‘no doubt’ moved to its present position at the time of the restoration by John Norton, in 1860-1 (Verey 2002, 285-6)

The font bowl is said to be c.1200, the chamfered stem and Perpendicular style octagonal base may be 19thc (Verey). Fryer suggests that the lower part of the bowl was ‘champered’ down to an octagon to meet a new octagonal pedestal made as some later date (Fryer 1910, 302). He divides the county’s fonts into those that were unmounted, and those that were mounted on a stem or pedestal, saying ‘it is quite probable that such fonts as those at Rendcombe, Ampney Crucis and Coates never had supports when they were originally made’. This, he believes, was because they were used for adult rather than infant baptism; the mounted fonts became prevalent when infant baptism was the norm (Fryer 1910, 287-90).