Whatcom Peak lies to the south of Whatcom Pass, at the head of the Little Beaver Creek drainage. Beckey describes the peak as an "associated outlier" of the Picket Range, separated by the the point of Perfect Pass to the south of the peak.

Take trails either from Little Beaver (hike in via Big Beaver/Beaver Pass from the Ross Dam trailhead off Highway 20, or take the water taxi ($135 from Ross Lake Resort to Little Beaver in 2016)) or Hannegan Pass (accessed from the Mt. Baker Highway 542 and FS Road 32) to Whatcom Pass. The North Ridge is accessed by heading directly south from Whatcom Pass. The south side route can be accessed from Whatcom Pass by a low orbit of the peak on the east, or from Easy Ridge to Perfect Pass.