Unintended birth is associated with adverse maternal and infant outcomes. In 2006, US Hispanics had the highest unintended birth rate (45 births/1,000 women) compared to other groups. One-fifth of US Hispanic women reside in Texas, yet unintended birth among Texas Hispanics has not been studied. The goal of this study was to describe the prevalence and characteristics of unintended birth in this population. Using data from Hispanic participants in the Texas Pregnancy Risk Assessment Monitoring System 2009-2010, we studied unintended birth in relation to demographic, lifestyle and partner characteristics. Adjusted prevalence odds ratios (POR) were computed for each characteristic and the analysis was stratified by maternal nativity (US vs foreign born). The weighted proportion of unintended birth was 49.5 % (CI = 45.9-52.6). In adjusted analyses, women aged 12-19 had a higher prevalence of unintended birth compared to ≥20 years (POR = 2.1, CI = 1.3-3.7). Unmarried (POR = 1.5, CI = 1.1-2.1), uninsured (POR = 1.7, CI = 1.2-2.3), and US-born (POR = 1.6, CI = 1.0-2.6) women had higher prevalence compared to married, insured and foreign-born women, respectively. Among US-born Hispanic women, higher prevalence of unintended birth was associated with being young, unmarried and experiencing psychological stressors within 12 months of giving birth; among foreign-born Hispanic women, higher prevalence was associated with lack of insurance. Efforts to reduce unintended birth in Texas might focus on young, single, uninsured and US-born Hispanic women. Analyses of other pre-pregnancy factors and health outcomes among Texas Hispanics could increase understanding of the differences we observed in unintended birth between US and foreign-born Hispanics.