The major provisions of the Affordable Care Act influencing health insurance coverage took effect this year. Residents of all 50 states who could not obtain affordable health insurance through their employer or in state insurance markets can now purchase coverage through the ACA’s Health Insurance Marketplace. Families earning between 100% and 400% of the federal poverty level are eligible for subsidies to purchase insurance in the Marketplaces. Individuals in families earning less than 138% of the federal poverty level are eligible for Medicaid if the state they live in elected the Medicaid expansion offered by the ACA. Under the law, almost all individuals are required to obtain health insurance coverage by March 31, 2014, or pay a penalty levied by the IRS in their tax return for 2014. Given that Texas has consistently had the highest percent of uninsured residents among the 50 states for several years, the insurance provisions of the ACA are expected to play a substantial role in providing coverage to the close to 5 million adults who reportedly lacked health insurance in the state in 2010-2011. However, technical problems plagued the electronic websites for the Health Insurance Marketplaces in each state when they opened in October 2013, and some of these problems still exist today. In addition, Texas declined the Medicaid expansion offered by the ACA, so that most adults in families earning less than 138% of the federal poverty level are ineligible for any public subsidies to purchase health insurance. In this brief, we track changes in health insurance status in Texas between September 2013 and March 2014. We find that the rate of uninsured adults ages 18 to 64 in Texas declined from 24.8% to 23.5%. The majority of this decline is attributable to an increase in the percent of adult Texans obtaining insurance through an employer. The proportions of adults with either Medicaid or individual private insurance both declined during this period. However, these percentages likely disguise significant changes in insurance coverage in Texas over the time period. By mid-March 2014, an estimated 746,000 Texans had obtained private insurance through the Marketplace. Of these, 225,000 (30.2%) were previously uninsured. Although a seemingly small proportion of Texans obtained insurance through the state’s Marketplace, the large absolute numbers had a substantial impact on increasing access to insurance coverage in the United States.