The federal government can afford to increase welfare payments to singles, the Australian Council of Social Services says.
Federal Finance Department estimates show welfare payment increases suggested by the Australian Greens would cost $13 billion over four years.
But ACOSS chief executive Cassandra Goldie says the government could save $5 billion over that time, if it just lifted the payment to singles by $50 a week and indexed the payment.
"It's about priorities," she said.
"The department's figure is misleading as it includes other costings for things that are not being called for."
Those things included increases to payments for couples.
A spokesman for ACOSS said singles were the most in need of a pay increase.
"The rate for singles has not increased in 20 years," he said.
Greens leader Christine Milne released the estimates on Monday night.