Under the Local Government Act 1894, parishes were no longer allowed to straddle borough boundaries and so the Mortlake civil parish was split, with the majority covering 1,554 acres (629 ha) outside the borough becoming the west of the Barnes Urban District and the part in the borough of Richmond, covering 329 acres (133 ha) forming a new North Sheen civil parish.
The coat of arms of the borough was granted on 19 June 1891. The arms is per fessgules and azure on a fessermine between in chief a lion passant guardant between two portcullisesor and in base a swanargent upon water proper; a representation of the ancient Palace of Richmond proper between two roses gules barbed and seeded proper.
The crest was a stag regardant proper, holding in its mouth two roses on one stem, one argent, the other gules, and supporting with the dexter fore hoof a shield or a wreath vert.[4]
The portcullises, roses and lion were all associated with King Henry VII, who brought the rival houses of Lancaster and York together and helped build the palace. The swan represented the River Thames. The stag represented Richmond Park and Old Deer Park, and the wreath the idea of municipality.[4]
Today the arms may still be seen in five places in Richmond: on The Richmond Arms' pub sign in Princes Street; in the façade of the former post office in George Street; in the façade of the Old Town Hall in Whittaker Avenue, next to the clock above the entrance; on the Richmond War Memorial, which is near the Old Town Hall; and above the proscenium arch in the Richmond Theatre. There is also an example on display at the Museum of Richmond.