Veterans, serving Defence force members and their families have 100 days to make a submission to the Royal Commission into Defence and Veteran Suicide.
With the deadline looming, one support service says it's "now or never" for people to have their stories heard.
The commission will conduct a 10th round of public hearings in Adelaide later this month, ahead of the October 13 deadline for submissions.
The Defence and Veterans Legal Service says it has already taken more than 2000 calls for assistance from people across Australia, but time is running out.
"It's now or never. I urge people to act now if they have been thinking about making a submission," the service's national director Jasmine Stanton said.
"The voices of current and former Australian Defence Force members and their families must be heard by this once-in-a-lifetime inquiry."
Calls to the free legal service have come from all states and territories, with more than 500 from both NSW and Queensland, 285 from Western Australia, 225 from Victoria, 183 from South Australia and 102 from Tasmania.
Despite the high numbers, Ms Stanton said she understood some people still felt uncertain about how to share their views and experiences.
She said the service's lawyers could help people draft their submissions and provide tailored legal advice about issues including privacy, confidentiality and legal protections.
On the final day of the commission's ninth block of hearings, chair Nick Kaldas said senior Defence leaders needed to adopt a more urgent approach to addressing suicide within their ranks.
Commissioner Kaldas said evidence to the inquiry seemed to suggest no systematic analysis of suicide deaths or behaviours had been developed by Defence to ensure the mental health and wellbeing of its people.
"The evidence presented during this hearing again raises serious questions as to whether leadership within Defence has been taking adequate and timely action in relation to responding to the very real and pressing issues of suicide and suicidality within its ranks," he said.
The commission's Adelaide hearings open on July 17. It will then convene in Melbourne from August 28.
