By the late 11th century, a simple single-room stone building existed on the high, open ridge upon which the village developed.

A series of medieval expansions doubled its size by the 15th century, and the present building has changed little since then—despite a Victorian restoration overseen by architect R. H. Carpenter.

A major addition was the heavily buttressed Perpendicular Gothic west tower, topped with a tall broach spire and containing a peal of ancient bells.

West Hoathly stands on a high ridge in the Weald, 4 miles (6.4 km) south-southwest of the ancient market town of East Grinstead.

Worth, now part of the Crawley urban area but originally a large parish with a Saxon church, lies a similar distance to the northwest.

[3] The area was already settled by the 11th century, and names recorded at that time include Hadlega and Hodlega — later standardised to Hodlegh and Hothelegh, then (West) Hoathly.

[6] It was situated overlooking the surrounding forests on the ridge which forms the watershed between rivers flowing north towards the Thames and south towards the English Channel.

[7] Within a century, the church underwent the first of several major structural alterations which have resulted in "seven different medieval styles [and] building periods" being represented.

[9] A pair of windows, one a lancet and the other a plain two-light opening set below a quatrefoil, were inserted in the north wall, around 1250; they are "a most remarkable example of the beginnings of tracery".

[11] Early in the 14th century, a sixth stage of rebuilding took place: this was a major redevelopment, possibly caused by fire or other structural damage.

[12] The narrow south aisle was rebuilt in the Decorated Gothic style[13] to make it wider than the adjacent Lady chapel[3] (this lasted longer than the rest of the contemporary work);[12] an arch was inserted to link the chapel and aisle;[6] diagonal buttresses were added to support the east wall of the chancel;[14] two "rather coarsely executed" windows were inserted in the rebuilt south wall; and a new south entrance, a holy water stoup and a piscina were inserted.

[12] At the start of the 15th century, a Perpendicular Gothic tower with "the usual shingled broach spire"[13] was built at the west end.

They removed many 17th-century features, added a porch and vestry (described in 1935 as "perfectly deplorable examples"),[17] tiled the floor[19] and re-roofed the nave and chancel.

A new set of altar rails were also installed, and were positioned to run straight across the chancel; they were not newly constructed, but dated from the late 17th century and apparently came from St Mary's Church, Barcombe.

[22][23] It is built of sandstone rubble quarried from the local area, and has a chancel, nave, Lady chapel and adjacent aisle on the south side, tower with an octagonal spire, vestry in the southwest corner and an entrance porch.

[3] The oldest fabric dates from the early Norman era: the west and north walls of the nave, built in about 1090, survive.

The east window of the chancel was altered during the 17th and 20th centuries, but has 13th-century origins in the form of chamfered vertical sections with moulded splays.

Also in the vestry are three early 17th-century cast iron grave tablets commemorating members of the locally important Infeld family of Gravetye Manor.

[27] The smaller window of Sir Galahad is by WE Tower of the workshop of Charles Eamer Kempe and is a single lancet in the south wall commemorating Arbuthnot's nephew Captain Archie Middleton who fell in the same action in 1915.

On the south side there are two further two light Clayton and Bell windows (1891) showing a) Mary Magdalene washing Christ's feet, b) Noli Me Tangere, and c) the Publican and the Pharisees.

[27] St Margaret's Church has an extensive terraced churchyard with far-reaching southward views across the Weald to the South Downs.

[19] An ancient Sussex custom, also encountered at a few other churches nearby (such as those at Lindfield and Ardingly), applied for many years at West Hoathly: every landowner in the parish was responsible for the upkeep of a specific section of the churchyard wall.

The Diocese of Chichester does not directly manage it: instead it is looked after by the Parochial Church Council, who (along with the Friends of the Churchyard Trust, an independent body) pay for maintenance and improvements.

The Bishop of Chichester was authorised to hold the advowson from 1346, but in the late 14th century (in 1391 according to one source)[41] the church was appropriated again by Lewes Priory.

This relationship ceased after the Dissolution of the Monasteries in 1538; the advowson then passed in turn to Thomas Cromwell, Anne of Cleves and then The Crown.