New Zealand is one of the few western countries which doesn't record the number of veterans who take their own lives, the Defence Force says.
The suicide rate for serving soldiers is lower than for the overall population but no figures are kept for those who have left the force.
Figures provided to RNZ by the Defence Force reveal three suicides in 2012 by serving personnel, and one in 2013.
Those are the cases confirmed by the Coroner.
Other cases remain under investigation, including the death of a soldier serving in Jordan earlier this year.
Defence Force chief medical officer Wing Commander Paul Nealis said the suicide rate for current military personnel was lower than that of the overall population.
"Now we do have active programmes around it, but I suspect there's a bit of a New Zealand psyche bit there in terms of military tradition, but there's also the quality of the leadership."
He said coronial decisions are three to four years behind suspected suicide figures.
But New Zealand, unlike most western countries, does not record the number of suicides by those who have left the forces, Dr Nealis said.
"There is feedback there that we need to start formalising."
He said servicemen and women, who suffered mental health injuries while on deployment, were highly likely to leave the forces within months of their return.
In February, former soldier Aaron Wood got a call to see if he could help find a missing veteran.
The man's psychologist had contacted Veteran's Affairs following a session with him.
Veteran's Affairs contacted the RSA who, despite their own grave concerns for the man's wellbeing, couldn't find him, Mr Wood said.
The RSA rang him to see if he could help.
The RSA said its welfare officer also went to help find the man.
Within two hours he and some ex-army mates, had found the man living rough in a park in Auckland.
"We wrapped an adhoc support network around him ... and the whole thing was done via Facebook."
While a potential suicide was avoided that day, Mr Wood is under no illusions about the scale of the problem.
"In the aftermath of that we realised that there were some grave dysfunctions within the RSA, and within Veteran's Affairs, and between those organisations.
"If it's happened once it's probably happened before, and if it's happened once it's going to happen again."
Within six days Mr Wood and other veterans launched No Duff, a non-governmental organisation dedicated to helping veterans.
In the six months since then, No Duff has amassed more than 200 volunteers, largely ex-military personnel.
The name is military slang for 'this is not a drill'.
Otago University Associate Professor David McBride said while there were no figures to prove it, but unless New Zealand was unlike any of its allies, there will be veterans here who suffer mental health problems, are homeless, in financial strife, or fall foul of police.
"People are slipping through the cracks and it seems to be an increasing and worrying trend that there's this increasing rates of suicide overseas and I think the New Zealand Defence Force is certainly keeping a pretty close eye on that."
Dr McBride said the university's Veteran's Health Research unit was working to collate information about veterans.
Government departments are also working to include veteran data into a statistics project called the Integrated Data Infrastructure, which works to collect anonymous information about New Zealanders.
*RNZ will have more on the care of contemporary veterans with mental health injuries, such as Post Traumatic Stress Disorder, on Insight this Sunday morning.