The route for 2023 splits into two on the south side of Westminster Bridge. Once over the bridge the red route continues on to the A23 and the blue route turns and runs along by the Thames and follows the route of 2022. Both routes meet-up just before Croydon.

Due to the Coronavirus (COVID-19) pandemic in 2020 changes were planned for the start and route. Due to the smaller entry the start was planned to be a rolling start in The Mall and with only one route, crossing the Thames at Westminster Bridge, but due to the pandemic the Run was cancelled.

In 2019 due to road works on Westminster Bridge the route continued to Lambeth Bridge. After Lambeth Bridge the route again split with the Red Route continued on to the A23 and the Blue Route turned right and run beside the river for a short way and at one point joining the A3. Both routes joined up just before Croydon.

Please note: - The drive down Constitution Hill, in front of the Palace and The Mall is for Veteran Cars only. Constitution Hill and The Mall are closed to normal traffic every Sunday.
The veteran cars are allowed to use London's bus lanes on the day all the way to Coulsdon. Drivers of "Modern" vehicles are advised to check times of each section before driving in bus lanes as the times do vary.

The two routes join together and then both joined the A236/A235 and rejoined the A23 at Purley. From Purley the route is via the A23 or the old A23 to Crawley for the official coffee stop.

After the coffee stop the route leaves the A23 for the B2114 to pass through Handcross Hill, Hammer Hill, then B2115 for Whitemans Green, B2036 for Cuckfield, A273 for Burgess Hill and Clayton Hill, then rejoins the A23 at Pyecome for the run into Brighton.

Up to 2014 the official finish was at Preston Park where the cars are required to stop and then on to the sea front and the "Finish Line", on Madeira Drive. In 2015 and on, it's straight on to the sea front.

On the day the Veteran cars are allowed to use Brighton's bus lanes. Like London (on the day) their use is only for public transport and veteran cars. "Modern" vehicles use the one-way systems.