The Fair Work Ombudsman alleges Coles underpaid 7812 employees between January 2017 and March 2020, some of them by up to $471,647.

The $115.2 million relates mainly to overtime entitlements for salaried managers at supermarkets and liquor stores in each state and territory.

Forty-five managers were allegedly underpaid by more than $100,000.

Coles will face the Federal Court accused of unlawfully failing to keep proper records including those related to employees' overtime hours.

"Businesses paying annual salaries cannot take a 'set-and-forget' approach to paying their workers," Fair Work Ombudsman Sandra Parker said on Thursday.

"Employers must ensure wages being paid are sufficient to cover all minimum lawful entitlements for the hours their employees are actually working and the work they are actually doing."

The legal action stems from Coles' disclosure last year to the Australian Securities Exchange it was reviewing the pay of award-covered and salaried employees.

It is accused of significantly underestimating how much money employees were owed. Fair Work said more than $108 million remained outstanding.

Coles faces penalties of up to $63,000 per breach proven.

The company said it had apologised to affected team members and incurred $13 million in remediation costs, with another $12 million set aside.

"To the extent that further remediation may be required, we will update the market accordingly," Coles said.

Australian Associated Press