A shortage of seats has meant Rhys Hughes regularly chooses to pass up his place on the bus to stay with the younger children and ensure they arrive at school safely.

The St Joseph's Lochinvar student would rather be at school on time, studying for his Higher School Certificate, but he can't bear the thought of leaving the other children stranded on the path with no way to get to school.

"[This was an issue] when I was in Year 7; McKeachies Run was a growing community and it has continued to grow," he said.

"We're sick of it because we've dealt with it from Year 7 to now and it's becoming a matter where we need to know that we're safe going to and from school.

"My school has been advocating for more buses because there's a growing amount of Year 7 students this year."

The school is aware of the bus shortage and a Transport for NSW spokesperson said the company, along with Hunter Valley Buses, was currently undertaking a review of school bus services from Rutherford and Aberglasslyn to St Joseph’s College, St Patrick’s Primary School and Lochinvar Primary School.

"The review will consider any changes in student numbers and travel patterns since the start of Term 1, and students and parents will be advised of any changes to bus services for Term 2," a Transport for NSW spokesperson said.

"Transport for NSW and Hunter Valley Buses apologise for any inconvenience to students and parents."

Rhys' mother Jenny said the issue was impacting everyone involved and hoped it would be resolved soon.

"Safety should be a top priority," she said.

"One child's safety is as important as anybody's.

"It's concerning for a parent to get that call.

"Not all parents have transport to get their children to school so then they're at a loss to try to get them to school. It's affecting a lot of people's lives, it's not just the children not getting to school, it's parents and carers."

In reference to a specific overcrowding incident last month, the Transport for NSW spokesperson said a subsequent bus was dispatched to pick up any students who were unable to board the service.

"Transport for NSW is aware of an incident on the morning of February 20, 2019, where the designated bus was unavailable and an alternative bus with less capacity was redeployed at short notice."