The M4 corridor is an area in the United Kingdom adjacent to the M4 motorway, which runs from London to South Wales. It is a major hi-tech hub. Important cities and towns linked by the M4 include London, Slough, Bracknell, Maidenhead, Reading, Newbury, Swindon, Bath, Bristol, Newport, Cardiff, Port Talbot and Swansea. The area is also served by the Great Western Main Line, the South Wales Main Line, and London Heathrow Airport. Technology companies with major operations in the area include Adobe, Amazon, Citrix Systems, Dell, Huawei, Lexmark, LG, Microsoft, Novell, Nvidia, O2, Oracle, Panasonic, SAP, and Symantec.

The M4, originally the London-South Wales Motorway, is a motorway in the United Kingdom running from west London to southwest Wales. The English section to the Severn Bridge was constructed between 1961 and 1971; the Welsh element was largely complete by 1980, though a non-motorway section around Briton Ferry bridge remained until 1993. On the opening of the Second Severn Crossing in 1996, the M4 was rerouted over it.