Dhirren Singh Randhawa, 19, from Encounter Bay, stood silently in the dock as he was sentenced on Tuesday in the SA District Court to one year, one month and seven days in jail, with a non-parole period of seven months.
The sentence was suspended on condition he is of good behaviour for two years and he was a banned from driving for 10 years.
Judge Joanne Tracey warned Randhawa if he breached the ban, it was "all but inevitable" he would go to jail.
Randhawa had pleaded guilty to aggravated driving without due care and leaving the scene of a crash at Goolwa Beach, south of Adelaide, on November 17, 2023.
Charlie Stevens died from an irreversible brain injury he sustained when Randhawa hit him with his car.
Judge Tracey said that in leaving the crash scene, Randhawa had reacted with "shock and disbelief".
He was also impacted by an incident in 2021, when he was attacked by a group of men and had feared for his life, which had made him nervous and vigilant when in public.
Grant Stevens said: "We are continuing to learn how to live every single day without Charlie." (Matt Turner/AAP PHOTOS)
The judge said in arriving at a sentence, she needed to "balance the matters personal to you, the circumstances and gravity of the offending, the tragic loss of life, the effect on Charlie Stevens' family and friends and the general sentencing principles and aims".
She did "not overlook a terrible loss that has been suffered".
"Charlie Stevens was only 18, and a bright future was ahead of him," she said.
"He was much loved and his family are and will forever remain grief stricken, nothing said or done here today will heal their pain."
Outside court, South Australian Police Commissioner Grant Stevens said this was "a very true statement".
Grant Stevens said his family was grateful for the SA community's support and sympathy. (Matt Turner/AAP PHOTOS)
"We're grateful that this part of the entire process is over. Each court date has been difficult, stressful and emotional for our family," he said.
"We're grateful that Dhirren chose to plead guilty to this offence because that brought this part of it to a conclusion much more quickly.
"We are continuing to learn how to live every single day without Charlie. It's not getting any easier."
The family was grateful for the support and sympathy of the South Australian community, he said.
"And we continue to receive that every single day," he said.
Expert reports, including toxicology results showed Randhawa had no drugs or alcohol in his system.
Dhirren Randhawa did not comment as he left court. (Matt Turner/AAP PHOTOS)
A psychologist's report noted he exhibited symptoms of trauma related to the crash and concluded he met the criteria for adjustment disorder with mixed anxiety and depressed mood.
Character references described Randhawa as reliable, respectful and conscientious.
He did not comment when he left the court.
In court on October 3, Randhawa addressed the Stevens' family, telling them that learning Charlie's life support had been switched off "was the most difficult thing I've heard in my life".
"To Charlie's mum and dad, seeing you on TV, talking about Charlie brought out deep sadness within me," he said.
