Nave arcades are largely late C13.
Substantial rebuilding in the C15 included the nave, aisles, N chapel and S porch.
EXTERIOR: The church is dominated by the richly decorated C13 tower
the C14 spire, which forms an important landmark in the town.
The tower is early C13 and has five, richly decorated stages with tiers of varied blind arcading and tall lancets in the bell stage.
The C14 broach spire has statue niches retaining their original statues and gabled lucarnes.
Otherwise, the exterior is largely of the C15 and has low pitched roofs and embattled parapets throughout, except for the N chapel, which has a steeply pitched roof with embattled gables.
The lower part of the chancel E walls is early C13, but the upper part was rebuilt in 1860, when the E window was replaced.
The rest of the N chapel was rebuilt in c.1380
it was given new windows in the C15, when the N aisle was rebuilt and the rood stair turret between the N aisle and chapel added.
The S aisle, S chapel and S porch are also C15.
The windows have a range of late C15 tracery forms, mostly with vertical tracery and cusped lights.
The C13 window in the vestry was brought from No. 17 St George's Square in 1881.
INTERIOR: The interior reveals the complex, multi-phase history of the church more clearly than the exterior, with evidence of rebuilding around an existing church from the early C13 onwards.
The early C13 tower arch is richly moulded and has stiff-leaf capitals.
The lower relates to the pre C13 roof
the other was probably for a roof built at the same time as the tower or perhaps when the aisles were added or rebuilt in the later C13.
Above the tower arch are two C13 openings with trefoiled heads, but it is unclear if these opened externally or internally, as they are below the lowest visible weather course for the former roofs.
The SW respond of the S nave arcade is also early C13 and similar in character to the tower, and was probably for an extension of an earlier arcade that was subsequently entirely rebuilt in the later C13, the date of the E respond of the S arcade.
The N arcade was rebuilt at the same time, as the E and W responds of the N arcade are also late C13.
The arches and the piers on each side were rebuilt in the C15, probably when the aisle walls were rebuilt and the clerestory was added.
The tower vault with panelled ribs and a central opening for the bell ropes was also a C15 insertion.
The chancel had reached its present length by the early C13, presumably replacing an earlier, shorter chancel whose presence may still be detected in the differing widths of the chancel S wall seen in the internal offset between the S chapel and the vestry.
The C19 chancel S window replaced a medieval window.
The N chapel, narrower than the present N chapel, and the western part of the S chancel chapel were added in the late C13.Shafts in the corners of the S chapel suggest that vaulting was intended.
The western arches to both chapels are late C13.
The N chapel was widened in the later C14, when the eastern arch to the N chapel was inserted or rebuilt
there are three tomb recesses in the N wall, one of which contains an effigy of c.1380.
The chancel arch was rebuilt and enlarged in the late C15, presumably at the same time that the rood stair turret and now lost screen were added.
The N chapel roof was ceiled in c.1480,
the chapel was further modified in the early C16 when the Phillips tomb and adjacent door were inserted into the NE chapel arch.
PRINCIPAL FIXTURES: The church was largely refitted in the C19, and the Arts and Crafts scheme of 1890 by J D Sedding is particularly fine, but it retains some medieval furnishings including an octagonal, carved C15 font, a C15 stoup outside the N door, a C15 piscina in the N chapel and another undated, medieval piscina in the S chapel.
There is a c.1300 statue of the Virgin in the N chapel.
A few fragments of C15 glass in the N chapel and N aisle.
The choir screen is also by the same architect, with a rood of 1920 by Howard Bailey, added as a war memorial.
Two lecterns by Watts.
Some very good C19 glass, including the E window of 1860 by Wailes & Co and the N chapel E window of 1890 by Christopher Whall.
The N aisle roof is also C15.
The steeply pitched N chapel roof is probably C14
Also in the N chapel, N wall, three late C14 tomb recesses, one with an elaborate surround and a tomb chest with a military effigy of c.
1380, probably for a male Brown or Usher, the others plainer.
There are also many good wall tablets of the late C17, C18 and C19.
HISTORY There was a church here by the C12.
The W tower is c.1220, but was built against an older nave.
The chancel was also rebuilt and extended c.1220.
The S arcade and aisle were completed in the late C13, when the N aisle and N and S chancel chapels were added.
There was a guild of St Mary founded c.1310 and another to Corpus Christi by 1350 that may have used the N chapel.
In the C14 the N chancel chapel was widened and the spire added to the tower.
The nave and aisles were rebuilt in the later C15, a substantial S porch was added, the chancel arch was rebuilt and enlarged, and new windows were added.
The N chapel ceiling was given by William Hikham and his wife c.1484, and they are commemorated by an inscription on its cornice.
It was further restored, and the chancel E wall rebuilt in 1859-60 by Edward Browning, and the vestry was rebuilt and the chancel refurnished in 1890 to designs by John Dando Sedding , a noted Victorian church architect who also an influential figure in the Arts and Crafts movement.
SOURCES Pevsner, N and Harris, J., Buildings of England: Lincolnshire , 2nd Edition, 693-5 RCHME Stamford , 23-27 REASONS FOR DESIGNATION: The church of St Mary, Stamford is designated at Grade I for the following principal reasons: * Parish church with fabric of the C13-C15 and evidence for an earlier church. * Outstanding early C13 W tower, one of the best of its type, with a very fine C14 broach spire, which plays a prominent part in Stamford's fine townscape. * High quality C15 work, including outstanding roof of c.
This List entry has been amended to add the source for War Memorials Register.