The Salvation Army says an annual survey has found more than half of respondents admitted skipping meals in order to pay for other necessities.

In preparation for this weekend's Red Shield Appeal, the organisation surveyed more than 1,700 people across Australia who had recently sought its help.

The survey found nearly half were selling possessions to make ends meet, one in four had taken on new debt, a third could not afford heating and more than a third could not afford medicine prescribed by their doctor.

Single dad David lives in a two-bedroom housing commission flat in Sydney's inner city with his three children.

His story is typical of many of the 1,700 people the Salvation Army surveyed.

David survives on a disability pension and says some weeks he struggles to put food on the table.

He cannot afford basic items like school shoes and weekend family outings are rare.

"Every time an electricity bill comes in or a gas bill comes in I always seek assistance because I can either afford the electricity bill or the gas bill or I can afford the food. I can't afford all of it," he said.

"So it becomes a nightmare where if you get paid you've got a choice - feed the children or keep the power on.

"Sometimes I will ring up an agency and ask for some help. And if they have any vouchers left they will say, 'we can help you with either electricity or food, we can't help you with both'."

David says even with winter approaching, the family is having to go without a heater.

"Things are getting much tougher, especially now it's getting a lot colder and the kids want a lot more," he said.

"They want the heaters working and everything else. Where I've come to now, I won't put a heater on in the house because I can't afford it."

Two of David's teenage children have serious medical conditions and he says paying for their medication takes priority in his budget.

He says the future is a worry.

"It's hard because I think the kids sit back and they look at me and I'm hoping that they don't follow the footsteps that I'm in because if they do, they'll always struggle for the rest of their life," he said.

"It makes you feel lonely and very heartbroken for them because I can't teach them to go and do what they need to do.

"They've got to try and do things like that on their own.

"If they look back at their parents they'll always travel the same boat."

More seeking help

Salvation Army spokesman Bruce Harmer says more people are seeking help from the organisation.

"Things are worse this year than in previous years and certainly those that are surveyed feel that as well," he said.

"Seventy-one per cent of those surveyed say that they're stressed about their future, so they're not expecting the future to be any better."

Mr Harmer says more people are slipping below the poverty line.

"In years past, we rarely saw working mums and dads come in to see us but over the last few years we've seen an increasing number of people who do have employment who are finding themselves also in need of some additional help," he said.

The Salvation Army's Warren Palmer says while there were a number of factors contributing to people's financial problems, one stood out.

"We know that utilities remain a constant challenge, with little relief evident in the future," he said.

"And 59 per cent of those people surveyed had to defer payments to utility providers, so that is a really big impacter on those people struggling by at the moment."