A wage strike at SARS has forced the closure of 20 branches.
Nehawu and the Public Servants Association have rejected an offer of 1.39 percent.
Workers embarked on the strike in May, demanding increases of around 12 percent.
But SARS says it doesn’t have the funds for the pay hike.
Unions say the strike will continue indefinitely if their demands aren’t met.
Meanwhile, the taxman is urging the public to make use of its digital services.