The 33-year-old suspect was arrested after a two-car collision on the A53 in Shropshire on Saturday.
A teenager was killed and her mother was among two people seriously injured in the crash which happened at Astley, near Shrewsbury, at around 4.15pm.
The woman was driving a blue Volkswagen Polo, heading from Shrewsbury towards Tern Hill, when it was involved in a collision with a white BMW M140i coming in the opposite direction.
A man believed to have been driving the BMW was arrested on suspicion of causing death by dangerous driving.
He has since been released on bail pending further inquiries, West Mercia Police confirmed, while a woman who was a passenger in the Polo remains in hospital.
Two air ambulances were sent to the crash which shut the A53 between The Dog in the Lane pub and Battlefield Island for six hours.
Bystanders performed CPR on the 19-year-old woman but she was pronounced dead at the scene.
Police are continuing to appeal for witnesses and anyone with information or video footage is asked to get in contact quoting incident number 378 of April 9.