 The Representation of the People Act 1918 provided that the constituency was to consist of the "Northfield and Selly Oak Wards and the part of King's Norton Ward which is not included in the Moseley Division" in the County Borough of Birmingham.The Representation of the People Act 1948 provided that the constituency was to consist of the "King's Norton and Moseley and King's Heath wards of the County Borough of Birmingham".Moseley and King's Heath wards had previously been part of the Birmingham Moseley and Birmingham Sparkbrook constituencies, as had the part of King's Norton ward which lay to the north of Bells Lane and to the east and south-east of the middle of Monyhull Hall Road and Brandwood Road.