Jack Nunn, aged 25, was driving a white Audi A5 which ploughed into a tree in Barnsley in the early hours of Sunday, June 20.
His partner, Hannah Elsworth, a 21-year-old nurse, also died in the crash.
It is believed the car struck a kerb before leaving the road and hitting the tree.
No other vehicles are thought to have been involved.
The young couple were pronounced dead at the crash scene on Huddersfield Road, Wilthorpe.
Jack was the co-owner of JJ's Tyres on Wombwell Lane, Stairfoot.
In a post in the company’s Facebook page, his business partner said: “Due to the sudden and devastating passing of my friend and business partner Jack and his girlfriend Hannah, the garage will be closed until further notice.
“My heartfelt condolences go to both families.
“We are all in complete shock and absolutely devastated.”