No. 1 and Attached Wall and Gate Pier

No. 1 St James's Street is a shop with a flat above, completed in 1791, with a late 19th-century extension and 20th-century additions. It was designed by John Palmer and built by Henry Street. The front of the building is faced with limestone ashlar, while the ground floor on the right is rendered, and the rear is a combination of render and ashlar. It has a concrete tile mansard roof, hipped to the right, and a coped gable wall to the left, featuring an ashlar stack with early clay pots, likely shared with No. 2 St James’s Street. A flat roof hides the 19th-century extension to the right.

The building sits at the junction of St James's Street and Julian Road. It has a wedge-shaped design and narrows to the right, with the extension continuing to narrow to approximately one meter in depth. The first floor has three plate glass, horned sash windows in plain reveals, the left window featuring a wrought iron balconette. A similar window is present in the extension. The second floor has two similar windows with stone sills, along with a blind window in the extension. The ground floor on the left has a late 19th-century timber shopfront similar to No. 2 St James’s Street, featuring a two-pane plate glass window with a moulded sill, a rendered stall riser, and a panelled door with beaded, moulded, fielded, and glazed panels. The surround has panelled pilasters, console brackets, a modillion cornice, and a blind box. The ground floor to the right is blind with a band course above. A single dormer window has a two-pane, horned sash with a moulded architrave and a weathered sill band which connects with Nos. 2 and 3 St James’s Street.

The rear elevation has four small 20th-century windows, and remnants of a painted sign are visible on the extension to the rear left. The interior was not inspected.

Attached to the building is an ashlar gate pier approximately 3.5 meters high, with a mitred cap, and a length of rubble wall about 2 meters high with ashlar coping. This wall originally served as a boundary to the Countess of Huntington's Burial Ground and is linked to a later 20th-century ashlar wall inscribed with “COUNTESS OF HUNTINGTON’S CEMETERY AD 1765”.

The property is historically significant as part of the incomplete St James's Square development. This development, built on land leased from Sir Peter Rivers Gay, exemplifies the application of picturesque principles to town planning. Nos. 1, 2, and 3 St James’s Street were built by Henry Street under an underlease dated 14 March 1791, lasting 96 years from 24 June 1790.