On Friday (September 15) police were called to the scene of a crash between a van and a pedestrian at the junction of Brighton Road and Woodfield Hill.
The driver of the vehicle stopped at the scene and was not arrested.
The pedestrian, a man aged 90, was taken to hospital in a life-threatening condition.
The man died in hospital on Tuesday (September 19).
His family have been informed and are being supported my Met Police officers.
Police have conducted enquiries and are appealing for anyone with information or who witnessed the incident to come forward.
Anyone with information should call the witness appeal line on 020 8285 1574 quoting the reference CAD 2909/15Sep.
A spokesperson for Met Police said: “Police were called at 11:35hrs on Friday, 15 September to reports of a collision involving a van and a pedestrian at the junction of Brighton Road and Woodfield Hill in Coulsdon.
“Officers attended along with the London Ambulance Service and London’s Air Ambulance.
“The pedestrian, a 90-year-old man, was taken to hospital in a life-threatening condition.
“Sadly, he died from his injuries on Tuesday, 19 September.
“His family have been informed and continue to be supported by officers from the Met’s Roads and Transport Policing Command.
“The driver of the van stopped at the scene. He was not arrested.
“Detectives have carried out a number of enquiries and are keen to hear from any witnesses who have not yet spoken with police.
“They are also asking for anyone with dash cam footage who was in the area at the time of the collision to come forward.
“Anyone who can help the investigation is asked to call the witness appeal line on 020 8285 1574.
“Information can also be shared with @MetCC on X. Please quote CAD 2909/15Sep.”