The Federation is the professional body for budgeting services, with 166 member organisations across New Zealand.
Their latest statistics show budget advisers offer almost 500,000 hours of budgeting advice in a year, about 580 hours per adviser, or 11 hours a week.
Ms Fox said when a budgeting client walks into a budgeting service, they usually had around $20,500 in debt, of which $3700 was overdue.
"It's the overdue debt that is usually the impetus for them to visit our budgeting service; a nasty letter from a creditor, the power has been cut off, or the repo man is knocking on the door.
"We can usually address the crisis debt first, before helping the client make a plan to avoid getting back into the same situation again."
The Federation allocates client debt into any of 11 categories.
Clients owed the most to mortgages ($150 million), government departments ($64 million), finance company loans ($61 million) and bank loans ($48 million).
The rapid increase in client figures could partly be explained by the global economic recession, but was also the result of the Future Focus legislation from Work and Income requiring some beneficiaries to complete a budgeting activity, Ms Fox said.
"We have been trying to work with Work and Income to manage this, but we're pleased [Social Development] Minister [Paula] Bennett announced a review of the way budgeting services are funded.
"We expect the Ministry of Social Development (who part-funds budgeting services) will consider the massive influx of Work and Income clients as part of their review.''
Ms Fox said little disasters such as a car or fridge breaking down, or having to buy new school shoes, could increase debt levels quickly.
"Sometimes you make the decision to pay the person that's threatening you the most first, which might not have actually been the most important thing to pay but you have to get people off your back, you have to have coping mechanisms."
Although clients were seeking help earlier than in the past, meaning their debt levels were lower, people now faced tougher financial circumstances, Ms Fox said.
"The basic outgoings of rent, power, food, petrol have risen...and people's wages just haven't risen.
"There's actually no money to address the arrears.
"The common thing that we really see is people that pay what they really have to pay [each week] and they've only got $50 left to feed a family of four."
Client demographics were also changing, with families who had gone from two reasonable incomes to one because of redundancies, or workers who faced a reduction in overtime hours.
"We're hearing people saying, 'I've never actually had to rely on a foodbank before and it's really uncomfortable having to do that'."
The worst affected areas were South Auckland and the Far North, due to the extreme levels of poverty.
Third-tier lending, pay day lenders and people with English as a second language getting into trouble with confusing credit contracts were common in South Auckland, while the Far North was "a very depressed area" with high rates of unemployment.
The 2010 Future Focus legislation meant beneficiaries accessing multiple special needs grants had to undertake budgeting, often through the Federation's service, which "blew our numbers out of the water", Ms Fox said.
The Federation received funding from the Community Response Fund, set up during the recession, but that money ran out in June this year.
Ms Fox said Minister Bennett then distributed a one-off $1.5 million injection into budgeting services for the coming year, however it was not enough to maintain services with continued high client numbers.
"On a national budget we've got just enough to maintain what we've got for this year.
"In the local areas we have got some of our local members having to cut back a bit because there's not enough money."
She admitted having one budgeting adviser on the national helpline was not enough "but that's all the money we've got".
Social Development Minister Paula Bennett said she was aware of the demand for budgeting services.
"That's why we boosted funding with an extra $1.5 million in the last Budget.
"The current review of budgeting services will provide a clear picture of the spread of services and where any gaps are so we can address those."
