Adopted 3 October 1933 on Geological Survey sheet 307A, Portland Canal, as labelled on British Admiralty Chart 2431A, 1868, and on BC map 1H, 1917.

Source: BC place name cards, or correspondence to/from BC's Chief Geographer or BC Geographical Names Office

Named July 1793 by Captain Vancouver in honour of William Henry Cavendish Bentinck, 3rd Duke of Portland (1738-1808), Home Secretary from 1794 to 1801. In 1903 the Canada-Alaskan Boundary Commission placed the boundary between Canada and Alaska along the middle of this channel.

Source: Akrigg, Helen B. and Akrigg, G.P.V; British Columbia Place Names; Sono Nis Press, Victoria 1986 /or University of British Columbia Press 1997

The Nisga'a name for Portland Canal, referring to the entire inlet, is K'alii Xk'alaan
A common fishing and food gathering place for all Nisga'a. The general area of upper Xk'alaan is a fused region having been occupied by both Nisga'a and Jits'aawit in the past. Decimated by both war and disease, the remaining Jits'aawit were taken under the protective wing of the Nisga'a Laxsgiik/Eagle chief, Sim'oogit Sganisim Sim'oogit (Mountain Chief). Total authority to the entire area thereafter (late 1800's), fell under the titleship of the Nisga'a, namely Sim'oogit "Sganisim Sim'oogit". [ts'im/ inside of, towards the inside; k'alaan/ at the back of (someplace)]. Sites up and down the inlet, on both sides, are named.

Source: Nisga'a Tribal Council / Ayuukhl Nisga'a Department, Aiyansh BC