Post Office, 29 Alloway, Ayr

21 Alloway in Ayr is a two-storey, two-bay terrace of gabled cottages designed by James K Hunter in 1903. The building features painted harl and has advanced cat-slide roofs with paired entrance porches. It includes low boundary walls with supporting columns, timber eaves, and decorative rainwater openings that connect the gables at the eaves.

On the northwest entrance elevation, there is a glazed timber door leading to the entrance porch of No 21. The bay to the left has been altered to create a shop entrance with a glazed timber door, and there is a bipartite window above it on the first floor. No 23 has a glazed timber door and a tripartite window at ground level, with a bipartite window above on the first floor. The ground floor of No 25 has an infilled entrance porch with a timber door, a split letterbox fanlight, and a single window to the left; there is also a bipartite window and a single window to the left with an advanced canted return, and a bipartite window on the first floor. To the left of No 27 is a timber glazed door, with a tripartite window to the right at ground level and a bipartite window aligned above on the first floor. No 29 has an altered shopfront featuring a glazed timber door to the right and shop windows to the left, with a bipartite window on the first floor. The ground floor bay of No 31 has a timber door to the left and a single window, with a tripartite window to the right and a bipartite window aligned above on the first floor.

The southwest and northeast elevations are gabled and blank, while the southeast elevation was not visible in 1999. The cottages predominantly feature 8-pane timber sash and case windows, although some modern glazing has been introduced. The roof is covered with rosemary tiles and includes stone skews, rooflights, coped ridge and gablehead stacks, and circular cans. The cast-iron rainwater goods are also present.

The interiors were not seen in 1999. The property is enclosed by predominantly iron railings atop a low coped boundary wall that surrounds the entrance elevation.