A wheelchair user says he was “forced to wet” himself when he was left at a bus shelter for an hour.
Ryan McDade said he was passed by three Pronto buses in Mansfield, Nottinghamshire.
The 20-year-old said he felt “dehumanised” by the drivers and that the experience was “humiliating”.
Bus operator Stagecoach East Midlands wrote to Mr McDade to apologise after reviewing CCTV footage adding “we do not condone this type of misconduct”.
Mr McDade had spent time in Mansfield on Friday and was trying to return to Portland College, a residential specialist college near Ravenshead.
The musical theatre student, who has cerebral palsy, said: “We were waiting about an hour and in that time three bus drivers just drove past, one of them even opened the door to the bus and just said ‘no’.
“We were waiting so long that I was forced to wet myself, which is really humiliating.
“There was a lady sitting next to me, I cannot tell you the embarrassment.”
Mr McDade suffers from curvature of the spine, and therefore cannot use public disabled toilets.
He said it was the first time he was “point-blank refused” entry on a bus, but he said there was space in the wheelchair area of the buses.
“It was dehumanising, getting on a bus [as a wheelchair user] is a nightmare,” he said.
“The bus is my way of having independence, so if somebody were to say ‘you can’t get on the bus’ like they did on Friday, it’s like somebody’s taking away that independence.”
Ceri Smith, policy and campaign manager for disability charity Scope, said: “It’s disgraceful that Ryan had to endure this horrendous experience.
“Public transport should serve everyone in our society, but disabled people are being let down every day.”
Stagecoach East Midlands operates the Pronto bus service.
In a written response to Mr McDade’s complaint, the company said it offered its “sincere apologies to Ryan”.
It added: “Two of our staff have failed to comply with the company’s policies in respect of both stopping for passengers and disability awareness.”
The drivers will be “interviewed under the company’s formal disciplinary procedure”.
A spokesperson for the operator added: “We are very disappointed that Ryan was let down on this occasion.
“We have also spoken directly to Ryan’s mother to apologise.”