Controversial unionist Kathy Jackson allegedly used union credit cards to misappropriate more than $660,000 for her own expenses including airline tickets, boutique hotel rooms and upmarket dinners while on a series of lavish overseas holidays.

Her alleged expenses, revealed in bank statements subpoenaed by the Health Services Union, also list large purchases at Melbourne department stores and liquor shops. Thousands of dollars were allegedly blown in single visits to some of the city's most exclusive bars and restaurants.

Health Services Union whistleblower Kathy Jackson arrives at the Royal Commission into Trade Union Governance and Corruption. Credit:AAP

The transactions relate to multiple union credit cards controlled by Ms Jackson and bring the total amount of members' funds she is alleged to have misused to more than $1.4 million.

Ms Jackson, the former Victorian HSU boss, rose to national prominence for exposing the credit card misuse of her predecessor, disgraced former federal MP Craig Thompson. He was convicted of fraud charges earlier this year for misappropriating about $24,000 of union funds.