Courtney Cowan, 19, and 25-year-old Lee Pickthall died in Thursday’s collision in Dumfries and Galloway.
Police Scotland said the Audi A6 was travelling on the A710 towards Dumfries when it seemed to lose control near Laneside Cottage and came off the road.
Emergency services were called to the collision at around 11pm but Mr Pickthall and Ms Cowan were pronounced dead at the scene.
In a statement issued via police, Ms Cowan’s family said: “We are devastated by the loss of our beautiful Courtney. She was a popular, lively young woman with a bright future ahead of her.
“Everyone loved her and our lives will never be the same again as we try to come to terms with her loss.
“We are overwhelmed by the messages of concern and condolences we have received at this sad time and we would like to thank everyone who has been in touch.”