Simon Millar, 45, is in a serious but stable condition in hospital after colliding with a Honda CRV on the A710 near the entrance to the Mabie House Hotel, Dumfries and Galloway.
The carriage was carrying bride Donna Pennycuik and her father Lawrence to the hotel for the ceremony, with Mr Millar's daughter Hannah also on board.
Miss Pennycuik and her father escaped the wreckage and helped Mr Millar while they waited for assistance.
Four ambulances and a helicopter were called to the scene and all four were taken to Dumfries and Galloway Royal Infirmary.
The 29-year-old bride, her father and Mr Millar's 18-year-old daughter were released from hospital after treatment for minor injuries. The bride and her father returned to the wedding and the ceremony went ahead.
A spokesman for the Scottish Ambulance Service said: "It's a miracle that they got out of with just minor injuries. They were determined that they would get back for the wedding."
The group on board the carriage are all from the Dumfries area. The driver of the car was not injured.
A local vet attended the collision and treated the horses for minor injuries, a police spokesman added.