The buildings within the Inn are grouped principally in two squares, with the remainder ranged around the gardens.
The buildings range in age from before the 18th century through to the 21st century, with the former group all being listed as of architectural and historic interest.
The Hall and Chapel occupy the site of the mediaeval manor house of the de Greys and their chapel. The present Gray's Inn Square was formerly two smaller courts, Chapel Court and Coney Court, separated by a range of buildings which perhaps marked a boundary of the original courtyard and was demolished in the early 17th century. South Square was formerly known as Holborn Court. The two northern terraces of Raymond Buildings and Verulam Buildings were both constructed on former garden land in the early 19th century. Field Court runs along the southern boundary of the Walks. Its western end was once closed by Page's Buildings, a range of tenements demolished in the late 19th century, which marked the former division between the grounds of the Inn and those of Warwick House. No structural trace remains of this, but the site of the house is now occupied by Warwick Place, which was not acquired by the Inn, while the site of its garden was, and is now occupied by Gray's Inn Place and the building used by the City Law School.
The Inn was badly damaged by bombing during the Second World War and the post-war buildings are a result of that damage with rebuilding taking place in the late 1950s. Being of more modern design, the facilities are superior to those of the pre-war buildings. However, the buildings of the latter group have their own particular charm due to age and layout. Most of the buildings consist of offices on three or four floors, with residential and overnight accommodation principally located on the top floors.