SIPTU members formerly employed at Rehab Enterprises in Raheen, Co Limerick will stage a protest outside the RehabCare office in Limerick on Tuesday.
The former workers say they are deeply frustrated at delays in the issuing of outstanding redundancy payments.
Thirty-eight workers lost their jobs at Rehab Enterprises in 2021 when it closed its logistics centre.
The Labour Court has recommended that the monies owed should be paid by the Rehab Group.
"Our members have not accepted their unfair treatment after years of loyal service," said SIPTU Organiser, Robbie Purfield.
"They expect Rehab Group to honour its obligations as a matter of urgency and pay them their outstanding redundancy entitlements," Mr Purfield said.
A spokesperson for the Rehab Group previously said that Rehab Enterprises is a private company and a separate legal entity from any other entities in Rehab Group.
The spokesperson said that the Labour Court recommendation was being taken through the appropriate internal governance process and that Rehab would revert to those impacted as soon as it was able to do so.