The Congress of South Africa Trade Unions (Cosatu) in Gauteng is expected to march to the Union Buildings in Pretoria on Friday to protest against e-tolling.
"We will march to the office of the president to bring an end to the e-tolling system," provincial secretary Dumisani Dakile said.
He said they were demanding answers from those who "took the decision to establish the e-tolls" and wanted to know why e-tolls were "so expensive".
Dakile added that the federation would unveil transport plans on Monday afternoon.
While they were expecting masses to join the march, they said it would be peaceful.
"People will be coming from different places across the province, but we will be gathering at Burgers Park in Pretoria," he said.
Dakile said the momentum to have the system done away with was growing, especially now that they were joined by the ANC and civil society organisations.
"We are quite certain because 95% are not paying this particular e-toll. We can tell without any doubt that there is not even a single department in Gauteng that pays for this [thing]. The momentum is very high, so people must continue to boycott [it]."
The march will be the launch of the action Cosatu intends to take to have the system dismantled.
Last week, the ANC in Gauteng reiterated its stance on the scrapping of e-tolls.
"Let there be no confusion, they are not part of the future of this province. We will have to work out how to pay for the roads but not through the e-tolls," Gauteng premier and ANC provincial chairperson, David Makhura, said.