The S door opens to a small half-glazed vestibule with leaded glazing. The interior is faced in tooled snecked stone with freestone dressings, including rere arches. The 4-bay nave has Decorated-style arcades of octagonal piers on square bases, pointed arches with a single order of chamfer, and a hood mould. A plainer pointed lower arch is to the tower. The 4-bay nave roof has collar-beam trusses on large corbelled brackets, with an emphasis on the joinery characteristic of Douglas. All but the narrower W bay also have subsidiary collar trusses. The underside of the roof is boarded, as it is in the aisles. Aisles have tie beams on corbelled brackets. In the N aisle E wall are stone steps with wooden balustrade to a vestry doorway, which has a shouldered lintel, and boarded door with strap hinges. In the S aisle W wall is a boarded door to the tower stair.
The wide, high pointed chancel arch has a continuous hollow moulding. The chancel is at a higher level, reached up steps, has ashlar walls and decorative tile floor. The 3-bay roof has trusses on corbels, decorated with relief angels and IHS monogram, and bracketed tie beams. Above the tie beams are moulded posts, including barley-twist queen posts. A high pointed arch with continuous chamfer opens to the N organ recess. Two sedilia and the piscina have lintels with relief ogee heads, and linked hood mould. A tablet in the S wall commemorates the gift of the church by Lady Henrietta Augusta Mostyn, 1898. The stone reredos is dated 1905 on a brass plaque in the N wall. It comprises a high-relief sculpture of Christ as a shepherd, under a cusped, ogee crocketed canopy between pinnacles on angel corbels, and outer half arches with traceried spandrels. The whole is framed by larger pinnacles, foliage cornice and brattishing. To the R and L are blind arcades of 4 bays with cusped main lights below reticulated tracery incorporating subsidiary trefoils and quatrefoils, and framed by end pinnacles and castellated cornice. The main lights are painted with the 10 Commandments.
The base of the tower is a baptistery with font of 1899 and stained glass in memory of Thomas and Sophia Mary Wallace. Around the font is a black-and-white diaper floor. The white marble font is by George Roberts & Son of Llandudno. It has a round bowl with a relief inscription around the rim 'The Lord bless thee and keep thee'. Four square panels, with relief moulded quatrefoils, a dove and one with the monogram 'T & SM W' are above detached Purbeck-marble shafts with marble bases and caps. These are subsidiary to the main pedestal of 4 clustered shafts. The octagonal base has a relief inscription around its rim 'Suffer little children to come unto Me'. The font has its original brass and wood cover.
Simple pews have shaped ends and incorporate umbrella stands, and are probably by Douglas. The front rank have blind traceried fronts. The polygonal wooden pulpit is on a stone base. It is panelled, with wider central facet depicting in low relief the resurrected Christ appearing to his 11 disciples. The choir stalls, also probably by Douglas, have ornate fronts of foliage panels over shallow paired arches on turned posts. Shaped ends include stylised poppy heads to the front rank. The low communion rail has balusters and arcading.
In the N aisle the E wall is a 1914-18 war memorial in the form of a Gothic reredos, by J.H. Hutchings, a local art teacher. It has 3 panels bearing inscriptions, above a corbelled shelf. The central arch has a cusped and crocketed ogee head, with traceried spandrels and brattishing. The simpler outer panels have foliage and castellated cornice, and diagonal pinnacles. On the N wall is a 1939-45 war memorial in the form of an engraved tablet in a freestone surround.
Most windows have stained glass, much of it by Lavers & Westlake of London. Chancel windows, however, are unsigned. The E window depicts the crucifixion. The N and S chancel walls depicts SS Matthew, Mark, Luke and John. In the other chancel S window, of the early C20, depicts Jesus appearing to Mary Magdalene. In the S aisle the 2 E windows are similar, one signed by Lavers & Westlake, 1899, shows the Good Shepherd, the other shows Christ as the light of the world, post 1903. In the S wall, from the E end, is a window on the theme of 'Suffer little children' with multi-racial group of children, post 1962; Christ healing the sick by Lavers & Westlake, 1905; Christ as a shepherd, with the resurrected Christ and Mary Magdalene, post 1934. In the W wall is a harpist and organist, by Celtic Studios of Swansea, 1982. In the N aisle, from the E end, the resurrected Christ appearing to his disciples, post 1904 by Lavers & Westlake; Christ appearing to Mary Magdalene, post 1961; Christ with Martha and Mary, 1964; Christ calming the storm, 1905; and 2 bishops, one with cross and eagle, one with crook (St Martin of Tours), by H.G. Hiller of Liverpool, 1934.
The baptistery has glass contemporary with the font. The W window, by Lavers & Westlake, 1899, shows emblems of the Evangelists, Pelican of Piety and Ark. The N and S windows, from the same workshop, show symbols such as Alpha and Omega, peacock, fish, phoenix and dove, as well as the Wallace family monogram.