THEY look real, but feel fake when they're handled.

Daily reports of counterfeit notes have been received by Mackay police since Sunday.

All cases involved 50 dollar notes and were detected at fast food drive-through locations, a supermarket and a North Mackay business.

Police are urging any person involved in cash handling to be vigilant and inspect all notes received.

Mackay District Crime Prevention Senior Constable Steve Smith said cases of counterfeit currency were unusual for the Mackay district.

"It's hard to tell if they are printed in Mackay," he said.

"But it seems there are more in the system.

"We have our officers working very hard on this particular issue."

Snr Const Smith said the fakes were hard to spot.

"Once we compared the counterfeit notes with the real ones, the difference became obvious," he said.

"The colours were faded, but they were also not quite as long and as wide as the genuine ones.

"The clear window on one particular note also became detached, which would not have happened to a real note."

Police urge residents to keep handling of suspicious notes to a minimum.

Snr Const Smith said residents who come into contact with a suspected counterfeit note should contact police.

"But they should also ask the person they received the note from to remain with them until police arrive," he said.

"It may be the case the person has handled the currency completely innocently.

"If the person has already left, detailed information would assist us with our enquiries."

Anyone with information should phone Crime Stoppers on 1800 333 000.