A company has been fined $48,000 over the exploitation of three Filipinos recruited as nursing assistants in Sydney aged care facilities.

The national workplace watchdog says Sydney-based Healthcare Recruiting Australia (HRA) deliberately underpaid one male and two female 457 visa-holders more than $15,000.

HRA placed the three workers at two Sydney nursing/aged care facilities in 2005 and 2006, where they provided residents with personal care and helped them with showering, dressing and eating.

The Workplace Ombudsman said HRA failed to pay full wages, casual loadings, penalty rates and holiday pay, and made unlawful decisions without the workers' consent.

"When they asked about their wages, they were fobbed off with false promises and threats," Workplace Ombudsman executive director Michael Campbell said.

"The workers have told how there were times when they were living on the charity of others and felt ashamed they could not pay their rent," he said.

They will receive full backpay amounting to a total of $15,811.

Mr Campbell said the court penalty should serve as a warning to other recruitment companies bringing in migrant workers.

The Workplace Ombudsman says it has investigated more than 400 matters relating to 457 visa-holders over the past two years, recovering more than $1.3 million in underpayments for overseas workers.

© 2008 AAP