The Coalition government is to target families, pensioners and disabled Australians with its controversial Centrelink "robo-debt" campaign, Parliamentary documents show.

The mid-year economic forecast tables published last week shows the government has booked savings of $1.1 billion clawing back overpayments of the aged pension and another $400 million from the disability support pension.

The tables also show the government believes it can retrieve another $700 million from hundreds of thousands of Australian families who receive parenting payment or have been paid the benefit in the past.

The moves could bring up to four million more Australians into the sights of the data-matching program, which uses an automated system to match information held by Centrelink and the Australian Taxation Office and calculate overpayments.