Lavaca Bay () is a northwestern extension of the Matagorda Bay system found mostly in Calhoun County, Texas, United States. The ports of Port Lavaca and Point Comfort have been established on the bay, and are the main areas of human habitation. Linnville was located on the bay until its abandonment after the Great Raid of 1840, and the major port of Indianola was found near the confluence with the main Matagorda Bay, until the town's final destruction following the massive hurricane of 1886. Smaller communities include Olivia, Alamo Beach and Magnolia Beach. Lavaca Bay is approximately northeast of Corpus Christi, about southwest of Houston, and southeast of San Antonio.