Geographic fed cattle markets are important because cattle are bulky and perishable, and production and consumption areas are separated. These characteristics make cattle transportation costly and can contribute to segmented markets. This study uses USDA-AMS reported fed cattle market price data from five U.S. regional fed cattle markets to investigate the effects of mandatory price reporting on spatial market integration. Results indicate these markets have been, and remain, highly cointegrated after implementation of mandatory price reporting (MPR). Following introduction of mandatory price reporting, the five regional fed cattle markets have become more fully integrated (i.e., prices tend to move more closely one-for-one following introduction of MPR).