Two former 7-Eleven workers who played a major role in speaking out for underpayment have received their back pay while another worker expects to receive $270,000 in wages from the convenience store chain.

Mohamed Rashid Ullat Thodi_, who is based in Geelong, had back pay claims dating back to 2007 and has allegedly received a five-figure amount after spending nine years pursuing his former boss for underpayment.

Another staff member, Pranay Alawala, risked deportation by speaking out about underpayment from two different franchisees in Brisbane. A report by Fairfax Media finds that Alawala has since received $33,000 in back pay.

This comes as only a week ago, a Senate hearing saw testimony from Allan Fels, head of the Fels Wage Fairness Panel, that a number of 7-Eleven workers who made back pay claims had been intimidated by franchisees and that at least one worker had been beaten.

A joint investigation by Fairfax Media and 4 Corners suggested systemic underpayment of workers at 7-Eleven's stores occurred at the complicity of head office in the exploitation of workers.

A sum of almost $2 million has already been paid out to current and former workers with the final back pay bill estimated to exceed $30 million.

Maurice Blackburn represented the two workers pro bono in making claims at the Fels Wage Fairness Panel. Employment principal Giri Sivaraman_ said the figures show the concerning extent of the “crisis”.

"Without exception every one of our 7-Eleven clients have said they were unaware of their rights, how much they should be paid or how many hours they should work," he said.

The underpayment debacle comes as three other 7-Eleven stores saw the consequences of underpayment in January.