XM Satellite Radio will add nine U.S. metro markets to its Navtraffic satellite navigation feature in the first quarter of 2006, bringing the total number of cities covered by the service to 31, the company announced Jan. 31.

The Navtraffic service, which is offered at a cost of $3.99 per month when packaged with XM’s $12.95 subscription price, provides traffic data directly to GPS navigation systems.