The crash occurred in heavy rain at around 10.45am. A silver Vauxhall Vectra, driven by a 27-year-old Crowborough woman, collided with a blue Mitsubishi Pajero, driven by a 30-year-old Uckfield woman.
The Vauxhall left the road and went down a bank, trapping the driver who had to be cut free by firefighters from Crowborough.
Both women suffered whiplash injuries and were treated at the Tunbridge Wells Hospital at Pembury.
The road was closed to traffic in both directions while the incident was dealt with.
The southbound carriageway re-opened at 12.10pm and the road fully re-opened at 1.12pm.