More than €3 million in unpaid wages was recovered by the Workplace Relations Commission (WRC) last year.
It marks a 75% increase on 2017 according to the Commission's annual report. The WRC received more than 15,000 specific complaints with more than 25% relating to pay issues.
A total of 4,050 working days were lost due to industrial relations dispute, which is the lowest number since 2012.
According to the Central Statistic Office, the number of employees earning less than the National Minimum Wage in 2018 totaled 24,500, down 100 or 0.4% from 2017.
The total number of employees earning minimum wage or less was 137,200, down 13,500 or 9% from 2017.
The results also showed that females were more likely to earn the National Minimum Wage or less. Half of those earning the NAtional Minimum Wage or less were aged between 15 and 24.