British Columbia is about 1.4 times smaller than Northern Territory.

Northern Territory is approximately 1,347,791 km² (520,385 sq mi), while British Columbia is approximately 944,735 km² (364,764 sq mi), making British Columbia 70.1% the size of Northern Territory.
Tip: This to-scale comparison of Northern Territory vs. British Columbia uses the Mercator projection, which distorts the size of regions near the poles.
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