Almost one in three Australians suffering from depression, anxiety or another life-altering mental health condition won't reach out for help, a survey shows.

The Beyond Blue survey of 5212 adults found 30 per cent of those living with a life-impacting mental health condition are unlikely to seek support from anyone.

Released on Sunday to mark World Suicide Prevention Day, the poll also showed 21 per cent of participants did not get professional help when they needed it or had put it off in the past 12 months.

Some 39 per cent of people cited costs as the reason for not getting help or delaying seeking it, while 30 per cent said it was due to waitlists.

Other barriers were thinking they would get better without support (27 per cent) and believing their problem was not serious enough to warrant it (24 per cent).

The data is concerning given the deep impact of poor mental health and suicide on people, families and communities, Beyond Blue chief executive Georgie Harman said.

"People need to know accessing support early, before they reach crisis point, can help alleviate stress, worry and isolation, and prevent depression and anxiety from getting worse," she said.

The poll was performed in November by the Melbourne-based Social Research Centre on behalf of Beyond Blue.

Beyond Blue offers a 24/7 support service, with almost 80 per cent of users reporting an immediate reduction in distress as well as ongoing feelings of diminished distress two weeks later.

Ms Harman's message to the community is it is never too soon to seek support.

"We know people can think their problems are too small or trivial, or they believe they are taking up valuable mental health resources," she said.

"But the impacts of depression, anxiety and emotional stress can be cumulative, and small problems can snowball and become harder to manage."

More than 3000 Australians die by suicide and an estimated 65,000 attempt to take their own life each year.

It equates to nine deaths and 180 attempts each day.

A national suicide prevention strategy is under development to reduce these numbers through preventing people from reaching the point of suicidal distress.

"There is a clear way forward and, while implementing the actions set out in the strategy will take time and commitment, there is no doubt it will save lives," National Suicide Prevention Office head Michael Gardner said.

Members of the public can register with the office to provide feedback on the draft strategy when it is released.

Lifeline 13 11 14

beyondblue 1300 22 4636