Patsy Harmston of the B.C. Government and Service Employees Union says starting wages are $15 an hour, a dollar less than 10 years ago, resulting in many of the workers having trouble making ends meet.
The union also says more than 40 per cent of the workers have been forced to cut services to their clients because of budget cuts.
The 24-hour job action will affect the Richmond-based Developmental Disabilities Association and the Burnaby-based PosAbilities, the two largest community social service agencies in B.C.
Agencies in Vancouver, Victoria, Prince George, Chilliwack, Coquitlam, Kamloops, Vanderhoof, Trail, Salmon Arm, Castlegar, Creston and Cranbrook will also be picketed.
The union says it wants to send a clear message to the B.C. government to stop putting the squeeze on programs and staff that help people with disabilities.