More Australians are turning to nannies and au pairs to mind their children to get around long waiting lists at childcare centres and avoid the high cost of multiple children in care, industry groups have said.

Census data shows the number of in-home carers is growing, adding to pressure on government to extend the childcare rebate to families using nannies and au pairs.

Charnwood mother-of-three Katherine Hayes, who employs an au pair, said she could not have continued her career without the flexibility and affordability provided by a live-in carer.

"Our boys are aged one, three and five and having all three in childcare four-days-per-week was going to cost $60,000 per annum," she said.

"It came down to about $39,000 after the rebate and we did it for a while but it was a total disaster."

Prime Minister Tony Abbott said before the last election that he was in favour of the childcare rebate being extended to nanny services.

The Productivity Commission is due to report at the end of the month its recommendations on whether the government should extend the childcare rebate to nannies but has already flagged its intention to refuse the rebate to au pairs.

Mrs Hayes said it was unfair to leave au pairs out of the equation.

"The au pair arrangement is very similar to family day care - where you do get the rebate," Mrs Hays said.

"Au pairs can also take some of the pressure off childcare centres which have really long waiting lists.'

Census data has shown that over the past decade a growing number of Australians have been employed as nannies, increasing from 5304 in 2001 to 6487 by 2011.

Australian Nanny Association spokeswoman Annemarie Sansom said she believed today's figure would be much higher.

Ms Sansom said some Canberra families were sharing nannies and splitting the costs to make it more affordable.

"The traditional workforce hours of 9am-5pm Monday to Friday have changed," she said.

"But childcare centre hours have stayed the same, so people who work late and on weekends in hospitality, retail, hospitals don't really have the option of using day care."

President of the Cultural Au Pair in Australia Association Wendi Aylward said the sector had grown substantially in the past five years; demand for au pairs had never been greater.

"CAPAA members have witnessed a twofold, sometimes threefold increase in inquiries for this period," she told the Productivity Commission's inquiry into Childcare and Early Childhood Learning.

"Many of these inquiries come from regional areas where there is little access to traditional childcare."