Some 25,000 federal tax workers launched rotating strikes last week after the Canada Revenue Agency and the Public Service Alliance of Canada failed to reach agreement regarding job security and pay issues.
Workers claim their wages are lower than those of their counterparts in the private sector.
A conciliation board had called for raises of 8.25 percent during a three-year contract, but the union said the agency last week came back with a three-year, 5.75 percent offer.
The strikers handle most government tax operations, including processing tax returns and answering questions from the public.
At the same time, 4,800 Parks Canada employees have been staging rotating strikes for slight more than a month. Additionally, the Canadian Food Inspection Agency and all Treasury Board groups could soon follow suit, meaning another 100,000 Canadian public servants would be on strike.