Premier Beehive near Wellington is reviewing payslips after one worker recognised they were underpaid for one shift.

The worker, who is a member of the E tu union, approached the union's lead organiser Mark James a month ago about the potential discrepancy.

After looking at it Mr James noticed the calculated holiday pay did not include extra earnings from allowances.

He said although the absolute amount of money this member missed out on might seem insignificant, the pure act is significant and should not be overlooked.

"It's $7 he was missing out for the one shift payment but had the employer done this over a number of years, the amount could have been significant."

Mr James advocated for the member and is still working with the employer to resolve pay issues.

He said if people would like to better understand their payslips they should look at the Holidays Act or talk to someone from their union, or the Ministry of Business Innovation and Enterprise.

"We are faced with a number of employees whose employers provide the payslip but make it very difficult to understand."