A spokeswoman said they had been considering the extended hours for some time, staff had been canvassing customers for months to gauge the level of support for the change.

"The feedback from our customers has been overwhelmingly positive and, as a result, Mount Isa locals will be able to satisfy their late-night chicken cravings from Monday, April 23," she said.

The additional trading times also mean added hours for current employees.

"They will be able to choose to take on additional shifts for the extended hours of trade to earn some extra cash," the spokeswoman said.

"We have also hired additional staff members specifically to cover late night shifts."

Mount Isa McDonalds Restaurant owner Stuart Resick said his store had enjoyed great success by opening 24/7 to meet the demands of shift workers in the city.

"We have been trading 24/7 for two years now and overall have seen it gain a positive for us, and the market in Mount Isa," Mr Resick said.

"It was a good decision for us and for the people in Mount Isa too who have access to our meals and drinks all the time."

Mount Isa Chamber of Commerce manager Zoe Dark said with many residents working long hours and shift work, the extended trading hours could improve the livability of the city.

"It could also benefit the tourism industry with many tourism hot spots opening longer hours to cater for tourists," she said.

"However, the last time we surveyed members on Sunday trading the majority were not supportive due to increased operational costs of opening for the extra trading day, the difficulty in providing additional staffing and the extra trading hours impeding on family and personal time.

"So the issue (of Sunday trading) needs to be given careful consideration and businesses need to ensure that it does not negatively impact small businesses."