Four-bay arcades to N and S aisles; shallow pointed arches with several orders of mouldings on short shafts of quatrefoil plan, with ringed capitals and bases. Chancel arch in similar style on short shafts with foliage capitals. Boarded and panelled wagon roofs with decorative bosses. Aisle windows with splayed reveals and sills; segmental stone head to W porch. Medieval chancel arch (between S aisle and chapel) is shallow with 2 orders of chamfers dying into chamfered imposts. Doorway to tower has segmental head of narrow voussoirs containing a door with pierced quatrefoils. An original Decorated window on N side of former Sanctuary is retained internally, and has 2 trefoiled ogee-headed lights under a later segmental head with original relieving arch of voussoirs.
C19-20 church furnishings including pews to nave and aisle with shaped foliate bench ends. Octagonal wooden pulpit to L of nave with blind arched panels with cusped ogee heads, and openwork above. In the N aisle is a screen to the vestry in a similar style. Bronze reading lectern to R. Chancel with diaper marble floor and choir stalls with decorative fronts, probably C20. Highly decorative stone reredos with 2 tiers of blind arches with cusped ogee heads and pinnacles. Behind the altar are 3 cinquefoiled arches with ballflower ornament which together contain a painting of the last supper. These are flanked by statues of angels in niches with ornate canopies. To their R are 2 niches containing a piscina and sedilia in the same style.
Octagonal stone font to W end of S aisle with pierced motifs including quatrefoils and flowers, on an octagonal stem and stone plinth. A brass tablet records that it was donated in 1872 by the Wilson family of Abergavenny. Rood screen under medieval chancel arch with ornate ogee and cusped openwork.
Chapel has encaustic tile floor and C20 choir stalls. Pink marble reredos by Halliday with foliate frieze to top; immediately behind altar are 3 niches under a cusped ogee canopy with pinnacles. The niches contain reliefs in white stone, Christ to centre flanked by angels.
There is much stained glass in the church, all early C20, and including the following: Chancel E window, Noli me Tangere, 1908. To L of chancel, World War I memorial depicting St Chad, by Hardman & Co. Further World War I memorials to W end; including to nave by Morris & Co., 1920. In chapel, Crucifixion to E window; nativity and Christ the good shepherd to S. S aisle L, to Martha Maria Lewis (d. 1924), by Kempe & Tower. To R, Suffer the little children, to William Henry Lewis (d. 1905) by Jones & Willis. To N aisle, the glass is by Powell's, Clayton & Bell, A L Moore & Son, and Heaton, Butler & Bayne.
There are also many wall monuments. These include plain marble tablets in the chancel to William Nicholl (d. 1756) and his son-in-law, Thomas Williams (d. 1810). Urn with drape on grey marble background to Marianne Jones (d. 1821) and her husband William. To S wall, from L, casket-shaped tablet to Wyndham Lewis of Green Meadow (d. 1838), and William Price Lewis of New House (d. 1840). Square tablet above with scrolled cornice to Margaret Knight (d. 1809) and her relatives. Plain tablet on corbels above, to other members of the Lewis family, and to R further similar tablets to the Jacob family, and to John Williams of Fair Oak (d. 1795). The N aisle has, from L, a casket with urn to Samuel Lewis (d.1814). To centre, a monument with pilasters and open pediment to Thomas Lewis of New House (d. 1764). To R, monument depicting a seated woman in grief, to John Lewis (d. 1850), also of New House and erected by his widow. This is by John Evan Thomas, a pupil of Chantrey.