The University of Tasmania has apologised for underpaying staff and pledged to repay current and former workers with interest.
The university is conducting a review into "inconsistent practices across the institution" and varying interpretations of complex staff agreements.
"First of all, I want to say sorry. Our people are central to who we are as an institution and what we do," chief people officer Jill Bye said in a statement.
"Our commitment is that we will be open with people and put things right.
"Once the review is finalised, we will communicate with any current and former staff who may be impacted. We will ensure that employees are paid any amounts owing, with interest."
Underpayments also relate to penalty rates not being correctly applied.
The university says it is one of several in the sector responding to historical issues of underpayment.
In November, Melbourne's RMIT university agreed to back pay thousands of academic casuals millions of dollars following a union dispute.
The National Tertiary Education Union claims the University of Tasmania underpayments date as far back as 2013/14.
"These underpayments potentially affect hundreds of UTAS staff over a number of years," Tasmanian branch secretary Pat McConville said.
"These underpayments may be just the tip of the iceberg."
The union says around half of the UTAS workforce is casual, with almost 70 per cent in insecure work.