British Columbia is the westernmost province of Canada. Situated between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, forests, lakes, mountains, inland deserts and grassy plains. British Columbia borders the province of Alberta to the east; the territories of Yukon and Northwest Territories to the north; the U.S. states of Washington, Idaho and Montana to the south, and Alaska to the northwest. With an estimated population of over 5.6 million as of 2024, it is Canada's third-most populous province. The capital of British Columbia is Victoria, while the province's largest city is Vancouver. Vancouver and its suburbs together make up the third-largest metropolitan area in Canada, with the 2021 census recording 2.6 million people in Metro Vancouver.

Canada has ten provinces and three territories that are sub-national administrative divisions under the jurisdiction of the Canadian Constitution. In the 1867 Canadian Confederation, three provinces of British North America—New Brunswick, Nova Scotia, and the Province of Canada —united to form a federation, becoming a fully independent country over the next century. Over its history, Canada's international borders have changed several times as it has added territories and provinces, making it the world's second-largest country by area.