The route is closed for roughly seven miles between Junction 9 Leatherhead and 10 Wisley where £300 million works are taking place.
The diversion route will take drivers off the motorway at Junction 8 for Reigate, through Tadworth, Ewell, Tolworth and the A3.
National Highways is asking people to take shorter journeys and to consider other forms of transport.
It’s also warning that drivers with non-ULEZ compliant vehicles may incur fines if they divert from the official diversion routes.
It is the second of five planned closures of the motorway, and comes after a section between junctions 10 and 11 was shut in March.