Young people currently face an 18-month wait to see a counsellor at Marymead with mental health providers anticipating services stretching further as a result of the pandemic.
Marymead's outreach program currently has enough resources to provide free counselling to 35 Canberra families in need of support, while 96 families wait for spots to free up.
As a result, children and teenagers are unable to access the early intervention associated with better outcomes.
Marymead team leader Carley Thomas said the problem wasn't a shortage of counsellors in Canberra, it was a shortfall in funding.
Over the Christmas period, the Narrabundah based health provider secured $41,000 in donations to help reduce wait times, with a goal of securing another $9,000 through its current appeal.
Its $50,000 target would cover the cost of 640 counselling sessions for children and young people needing mental health services through its New Horizons program.
The program takes a more holistic approach to young people's mental health than one-on-one counselling, through the involvement of family members and the school community.
Ms Thomas said Marymead was one of the only health services in Canberra which offered outreach because it recognised things like transport or even agoraphobia could act as a barrier to seeking help.
"We acknowledge that with mental health concerns for a young person that doesn't exist in isolation," she said.
"It might be that the child is suffering from anxiety or depression but that comes because maybe mum or dad suffer from anxiety and depression.
"New Horizons sees the young person at the centre of the therapeutic intervention but it would also work with mum and dad to see what was going on with them, maybe the siblings as well, or any other key person who is significant to that child's success."
Ms Thomas said if people are waiting on the waitlist for 18 months their problematic behaviours are becoming more entrenched and they're more at risk of receiving a formal mental health diagnosis.
Marymead has identified a gap in mental health services in Canberra for children between the ages of eight and 12, Ms Thomas said.
She used the example of a 10-year-old they are currently working with to demonstrate how their services differ from a more traditional one-on-one approach.
"She comes from a trauma history and she has had exposure to family violence, her parents are now separated and as a result of that she presents with anxiety and depression.
"As well as working with the child the counsellor has been able to speak with her parents separately about trauma and the impact that has on their child."