Ex-service personnel are being left homeless because local councils do not prioritise them for housing, campaigners have said.
The campaign has been backed by military support groups
The Royal British Legion said it had received 1,485 calls from homeless ex-service personnel in the past year.
A campaign has now been started by an army mother who successfully fought to get free postage for overseas troops.
Council officials insist the law ensures they must assist service personnel with their housing needs.
Theresa Theobold, who won her campaign for free post to UK troops in Iraq and Afghanistan, said she was struck by how many ex-servicemen and women suffered problems with housing.
"It's disgraceful that people who served Queen and country are returning home to find they can't get on the council housing ladder," she said.
"Giving them somewhere to live is the least local authorities can do."
Simon Hodge was medically discharged and has had problems finding somewhere to live ever since.
He has three children and a wife to support but says he has been told he is not a priority for council housing.
"I haven't been given any support in finding somewhere to live and had no idea about the sheer cost of renting. I feel my family is at breaking point," he said.
Former corporal Joseph Maguire has also been affected.
He says that when he left the Army he applied for council housing with Croydon Council but was told he was not a priority case and faced a very long waiting list.
He is currently staying with his mother and cannot afford either rent or a mortgage.
In a statement, Croydon Council said it had no record of Mr Maguire's application but would be happy to see him in the New Year.
A council spokesman said it did prioritise former army personnel, moving them up the housing register when their leaving date is known.
The campaign has been backed by military support groups such as the Royal British Legion and the Soldiers, Sailors, Airmen and Families Association (Ssafa).
In London alone, the legion believes there are 2,500 people who used to be in the services who are homeless.
The legion's director of welfare, Sue Freeth, said: "Councils are letting former soldiers down and don't realise the kind of sacrifice they have made for the country.
"Local authorities should give priority to all servicemen and women. They need to be cared for."
Athol Henry from Ssafa says it gets hundreds of calls every year from people worried about housing.
Local authorities admit that trying to juggle the demands for housing is difficult and controversial.
The Local Government Association and the Convention of Scottish Local Authorities said the housing needs of all former service personnel were a priority.
It is the responsibility of individual councils to decide how to prioritise but there is a legal requirement to help ex-service personnel with accommodation.
The LGA said: "This does not guarantee every former soldier will get a council house because not all authorities have their own housing and the council has to balance the needs of all vulnerable people living in the local area."
The Communities and Local Government department said the government had invested £300m in preventing homelessness and there had been a 73% drop in the numbers sleeping rough.
A spokesman said: "We know that most veterans make a successful transition back into civilian life. But we are committed to helping those who find it more difficult.
"This is why former service personnel are already a priority group for homelessness assistance under government guidelines if their service has made them vulnerable to homelessness."