British Columbia is about 1.4 times smaller than Northwest Territories.

Northwest Territories is approximately 1,346,106 km² (519,734 sq mi), while British Columbia is approximately 944,735 km² (364,764 sq mi), making British Columbia 70.18% the size of Northwest Territories.
Tip: This to-scale comparison of Northwest Territories vs. British Columbia uses the Mercator projection, which distorts the size of regions near the poles.
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