The two companies had appealed the tribunal after the competition bureau rejected Shaw's proposal to sell Freedom Mobile Inc to rival Quebecor Inc's (QBRb.TO) Videotron unit for C$2.85 billion to facilitate the deal.
However, in its Thursday ruling, the tribunal said such a sale would allow Videotron to expand in new markets and ensure competition remains robust.
"I am very disappointed that the Tribunal is dismissing our application to block the merger between Rogers and Shaw," Matthew Boswell, Commissioner of Competition, said.
The antitrust commissioner could still appeal after the tribunal lays out the details of its decision over the next couple of days.
Rogers-Shaw and Quebecor now await approval from Industry Minister François-Philippe Champagne to transfer Freedom Mobile's spectrum license to Videotron.