Abstract: | Do switching costs reduce or intensify price competition if firms charge the same price to existing and new consumers? I study 800‐number portability to determine how switching costs affect price competition under a single price regime. AT&T and MCI reduced their toll‐free services prices in response to portability, implying that reduced switching costs increased competition. Despite rapid market growth, gains from higher prices to “locked‐in” consumers exceeded the incentives to capture new consumers. Prices on larger contracts dropped more, consistent with greater lock‐in for larger users. Price changes between portability's announcement and implementation are consistent with rational expectations. |