Transurban will cut a range of fees it charges motorists using CityLink – but there's a catch.

From September 1, drivers on CityLink using Visa or MasterCard to pay their tolls will be hit with a new transaction fee.

Leaked Transurban reports show the toll road operator predicted in 2016 that, thanks to the volume of cars using CityLink, these fees would raise revenue of around $2 million from drivers annually.

Melbourne’s other toll road, EastLink, charges no credit card transaction fees.

The Age last week revealed Transurban raises tens of millions of dollars each year from the fees its charges motorists.