The earliest part of this Anglican church is the chancel arch, built in c.1220. Above the arch there is an unplastered patch which contains faint traces of wall painting. Fragments of medieval floor tiles were found in 1900 beneath the chancel floor; the stone tiles in the chancel were removed in 1974. The church had a new chancel by the 14th century and very fine vaulting can be seen. The bosses are carved with St. Michael, Abraham, a pelican and a mermaid, among others. There is a priest's door on the north side through a buttress. The burial crypt under the chancel has been bricked up.
The South transept was built in 1300. It was a chapel separated by a wooden screen; the James Long monument was placed where the altar had been. There is a door and upper opening to the former rood screen; the lower door was enlarged as a squint for the transept.. There is a piscina which is partly painted and the remains of a moulded opening (possibly a frame for the painted reredos between the east windows). The font is of early 13th century date and would have been situated in the earlier chapel. There is an oak cover made in 1900. The chest of Eliza Compton's father can be found below the west window, dated 1836. Eliza gave a legacy in 1881; her father had been a church warden. The south transept tie beam roof is dated 1787 and the date 1878 was carved in the roof beam. The pews were removed in 1980 to create a meeting place.
The south aisle received extensive rebuilding and enlargement in the 14th century. Freestone from Hazlebury quarry was used for the building works. During the 15th century a west tower and embattled parapet were built in the south aisle, with the chancel roof being repaired in 1478. The original west door and turret stairs still survive. A gallery was built in the tower in 1724 but removed in 1864 to make way for a church organ. The holes in the walls for the supporting beams can still be seen. The earlier gallery organ was removed and the present organ was made in 1910 -12. Regular payments were made to an organist from 1840 onwards. The east window is 19th century. The heads in the east side windows have 14th century angels holding crowns. There is a flagged floor and the south aisle roof is 1791.
The porch was added in c.1430 in the Perpendicular style and has exceptional four centred stone vaulting. It is almost unique for its period in a village church. The heads on either side of the doorway were said to represent King Alfred and Queen Ahlswith. Urchfont was given to the Nunnery of Winchester in c.900; the Nunnery had been newly founded by Alfred's queen, hence the stone carvings.
In 1523 one parishioner, John Bent, tailor of Urchfont, suffered martyrdom at Devizes for denying the doctrine of transubstantiation.
In the north transept an iron register chest is inscribed 'Erchfont Wilts 1813, Arthur Meyrick, Vicar. W. Wild, W. Horroway, Church Wardens'. The north aisle roof is 17th century. The north transept is now the vestry and organ chamber. There are scratch dials on the walls of the north and south transepts.
The piers of the nave arcade may be of a 13th century date; the dimensions of the nave suggest it may have been laid out at that time. High in the arches of the nave there are hooks for oil lamps- electricity was not installed until 1935. Before this there were also two stoves, one near the pulpit and one near the pillar by the south door. For the past 18 years at Christmas, 450 candles have been lit (one for each house in the village). The church was re-pewed in 1840 and a dado rail was added. These pews were replaced by open pews in 1864. In 1899 the dado rail was removed and in 1899 to 1900 the church was restored by C. E. Ponting. The present pews are double clinkered, an unusual design. Churchwardens' staves were bought in 1918.
There is an oak altar in the sanctuary, given as a gift in 1864. The bier is dated 1750. The pew nearest the organ was removed in the early 19th century, most likely to enable the bier to be turned at the end of the funeral services. The bier is now displayed at the Lackham Museum of Agriculture and Rural Life. The pulpit was given in 1864 by the Watson-Taylor family of Urchfont Manor.
There are monuments inside the Church to Thomas Ernle (d.1725), Robert Tothill (d.1753) and John Long (d.1768). In 1553 the chalice of 14oz was allowed to be kept by the church. In 1969 the Church plate consisted of: two silver chalices, one dated 1560, the other 1827, a paten of 1726, flagon of 1764, alms dish of 1845 and a pewter alms dish of 1837. There were four church bells in 1553. The earliest surviving bell is possibly 14th century and is the treble of the peal of eight bells in 1969. The tenor is dated 1610. Of the other bells, three are of a 17th century date (William Purdue of Salisbury); two are 18th century (Abraham and Abel Rudhall, Gloucestershire) and one 19th century (C. & G. Mears, Whitechapel, London). The peal was rehung in 1933. The belfry roof timbers are of 1805 and 1835. Twenty four hand bells were acquired in c.1980.
Parish registers from 1538, other than those in current use, are held in the Wiltshire & Swindon History Centre in Chippenham.
The House of Nunnaminster formally appropriated Urchfont Church in 1382. It retained the appropriate rectory until 1536 when it was acquired with the prebend and advowson of the vicarage by Edward Seymour. By 1478 a parcel of land called Rector's Close had been allotted to the vicar. In the later 17th century and in 1842 there were one and a half acres. A survey of 1650 describes the rectory as having a hall, parlour, kitchen, buttery, three chambers, a barn, stable, garden, orchard and a yard. It also contained 'a pightle of pasture adjoining containing by estimation 2 acres'. Part of the house now known as 'The Old Vicarage' is the house of 1650. Tenant farmers farmed the rectory land in the 15th, 16th and early 17th centuries. Later in the 17th century the rectorial estate had 20 acres in open field called 'Dunfurlonge'. In 1784 it included Lower, Middle, Hither and Little Glebe, north of Glebe Lane (Crookwood Lane). The rectorial estate passed to the Ecclesiastical Commissioners in 1867. In 1873 the vicar moved to Potterne where he had a 'much more comfortable residence'. Thirty five acres of land was offered for sale in 1892. It was sold off in small lots over the next 32 years.
Urchfont vicarage was enlarged in the early and late 19th century. The new vicarage was built on land to the east of the church, called 'The Rectory' in 1968/9. The Sunday School Club, the 'Garden Gnomes', meet in the summerhouse; they have summer outings and Christmas parties. There is a church choir summer outing. In the 1990s the church organised events such as the Rector's Fete Week in Urchfont in June. It included an open air service by the pond at 6 pm with the Salvation Army Band, a fete in the rectory grounds with a children's fancy dress competition beforehand and a cricket match. There was also an evening with the bell ringers' in Wedhampton.
In 1989 the benefices of Urchfont with Stert, Chirton, Marden, Patney and Wilsford united to form a new benefice of Redhorn Team Ministry. The parsonage house for the rector is in Urchfont.