A casual hospitality worker’s weekend penalty rates of about $40 an hour will be protected under a bid to prevent take-home pay from being shaved.

Measures to enshrine penalty and overtime rates in law will be introduced in the House of Representatives on Thursday by Employment Minister Amanda Rishworth.

The bill aims to prevent variations to awards that would result in lower pay for workers.

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“What this legislation will do is make sure that the safety net, which is our award system, can’t be eroded,” Rishworth told Sunrise viewers on Thursday.

“At the moment there’s a number of applications in front of the Fair Work Commission trying to erode the penalty rates and overtime of those workers who ... really are low paid (and who) rely on the award.

“So, what this legislation will do is protect those who rely on penalty rates, rely on overtime, because this often makes up a very large amount of their take-home pay.

“We think this is really important to put beyond doubt that you can’t strip away penalty rates and overtime from our safety system.”

Rishworth said the bill essentially means penalty rates cannot be rolled into one and lumped into a base salary.

Labor’s promise

This will be among the first pieces of legislation introduced by Labor in its second term of power following the May 3 federal election.

Workers can be entitled to higher rates of pay when they are required to work particular hours or days including weekends, public holidays or irregular hours.

While rates can vary depending on an employee’s specific award or agreement applicable to that industry, common pay rates for workers on a Sunday are double time (200 per cent) or time-and-a-half (150 per cent).

A calculation of rates on the Fair Work Commission’s website shows, for a casual hospitality worker, common penalties for a shift on Saturday to be $40.85 per hour, while a day’s work on Sunday could bring in $47.65 per hour.

Albanese’s pledge

Protecting penalty rates was an Albanese government election pledge.

Rishworth said the bill will ensure the wages of about 2.6 million award-reliant workers are protected.

“If you rely on the modern award safety net and work weekends, public holidays, early mornings or late nights, you deserve to have your wages protected,” she said.

“Millions of hard-working Australians rely on penalty rates and overtime rates to keep their heads above water, which is why this bill is so critical and should receive the support of both the opposition and the Greens.”

Labor’s planned changes came after peak retail and business groups put forward proposals for large companies to opt out of providing penalty rates for staff in exchange for a raise on base levels of pay.

Opposition employment spokesman Tim Wilson said the Coalition supported penalty rates.

“We will work through the legislation to make sure we consult the businesses and those it’s going to impact to get the best outcome,” he told AAP.

Wilson said the absence of a regulatory impact statement, which lays out the potential impacts of the proposed changes, meant consultation was even more important to ensure it would be part of the future success of the economy.

The Coalition also wants to assess how the changes would interact with the Fair Work Commission, which would be required to apply the new rules in addition to the modern awards objective in making its determination.