Wage deductions are only legal in a few circumstances, including if an employee has agreed to or requested the deduction in writing, That can be varied or withdrawn at any time - even if the original consent was included in an employment agreement.
Last November Masterton Night'N Day employee Kerry McIvor sparked national outcry after going public about having wages docked by Gull petrol service when customers drove off without paying. Several complaints by Gull employees followed and up to 29 staff nationwide were reimbursed.
Meanwhile, the Minimum Wage Act outlines strict requirements for minimum pay.
It prohibits deductions that mean employees end up with less than the hourly minimum for hours worked.
Masterton employment lawyer Adam Parker expected employer ignorance played a part. "I don't think there would be many employers who are intentionally breaking the laws," he said. "They're probably just not up on the latest changes to the laws."
Employers had no choice but to bone up on the laws, he said.
"Employers just have to keep up to date. Changes to minimum wage are well publicised and all that information is available on the ministry website.
"If [the ministry] keep pushing the message it should eventually get through."
Nationwide 1910 complaints were made to the ministry under the Minimum Wage Act between July 2012 and February this year. A further 733 complaints were made under the Wages Protection Act during the same period.
The accommodation and food services industry was the biggest offender, followed by the agriculture, forestry and the fishery industry.
Council of Trade Unions president Helen Kelly said the complaints would only hit "the tip of the iceberg" of the number of law breaches.
"That's only the people who can actually get through and complain and feel confident in doing that," she said.
"These are the worst forms of exploitation in New Zealand as the minimum code, which employees rely on, is being broken."
She wasn't surprised the accommodation and food services industry had the most complaints. "It's the vulnerable workers - migrants and students - that suffer the most.
"Employers know how to charge for things and run their businesses. This is deliberate exploitation of vulnerable workers."