Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
We estimate geographic barriers to trade in nine service categories for Canada's provinces from 1997 to 2007 with novel high‐quality bilateral provincial trade data. The border directly reduces average provincial trade with the United States relative to interprovincial trade to 2.4% of its borderless level. Incorporating multilateral resistance reduces foreign trade relative to interprovincial to 0.1% of its frictionless potential. Geography reduces services trade some seven times more than goods trade overall. Surprisingly, intraprovincial (local) trade in services and goods is equally deflected upward, implying that the border increases interprovincial trade much more in services than goods.