Underpayment of wages claims must be made within 6 years of the date that the payment became due, however only 3 years for unpaid Long Service Leave claims.
To check your rate of pay, check your contract, enterprise agreement, or award. If you are uncertain, contact the Fair Work Ombudsman, or use their pay rates calculator tool on their website called Pay and Conditions Tool (PACT).
The national minimum wage as at 1 July 2021 is $20.33 for full time and part time workers and $25.41 for casual workers (includes 25% casual loading).
Under the Fair Work Act 2009 (Cth) employers have to maintain employee records of pay and hours worked for seven years [s 535]. You also have the right to receive a record of your pay (payslip) within one business day of your pay day [s 536]. You must also be paid at least monthly and to be paid in money (not in goods or services) [see ss 323-327 generally about your rights to pay and permitted deductions].