English: The Domesday book mentions a church at Westbury and there was probably a Saxon church before it. There is evidence of the existence of a Norman church between 1109 and 1120 when the church was given by Henry I to Salisbury Cathedral. It was enlarged over the years with Chantry chapels and an enlargement of the chancel and transepts.

A large part of the church dates from the early fifteenth century. It was restored in 1847.

It is a large cruciform church with a crossing tower and embattled nave of four bays with clerestories which were added in the early sixteenth century. The line of the old steeply pitched roof is still visible. There was also once a gallery at the west end of the nave which also housed the organ, and this was dismantled in 1845.

The original tower was extended to its present height of 84 feet sometime in the fifteenth century. There are eight bells, and it is the third heaviest peal of 8 bells in the world.

The chancel has a steeply pitched roof with stone tiles, it was extended in the fourteenth century and again in the sixteenth century to its present size. The west front has a small porch and a large elaborate window. There is also a south porch which is of two stories and has a Lierne vault.

The south transept was extended around the thirteenth century for the use of the Lords of the Manor of Westbury, the Paveleys, and two members of that family are interred within. There is a monument to Sir James Ley and his wife Mary.

The Lady Chapel in the south east part of the church was built in the fourteenth century for the use of the Cheney family. It then passed on to the Willoughby de Broke family and later to the Phipps family. In 1892 it was made into a Lady Chapel

There are several monuments and tablets in the church.

The font is octagonal from the perpendicular period with panelling and Shields.

In 1968 water was found running under the church which caused the tower to lean, and it was in danger of collapsing. The foundations had to be stabilised to a depth of 55 feet. The church reopened in 1969

There is a three manual organ, originally by Hele, rebuilt by Stephen Cook in 2001.