The CBC will not be permitted to play paid advertisements on two of its radio networks as of Thursday.
The CRTC rejected the CBC's application for an extension that would have allowed it to continue playing ads on Radio 2 and ICI Musique, formerly Espace Musique, until August 2018.
Canada's broadcast regulator ruled that the CBC failed to demonstrate it continued to invest in radio, which was part of the criteria for allowing it to play paid ads.
The CRTC also said the CBC no longer needed revenues from paid national advertisements due to the Liberal government's commitment to give the public broadcaster $675-million over five years.
The CBC responded that the government's reinvestment of $75-million this year and $150-million in subsequent years is vital to stabilizing the corporation, but said that it still depends on commercial revenue to finance its services.
The CBC said implementing its 2020 strategic priorities to make its programming and services more Canadian, local and digital will require a combination of government funding and commercial revenues.