In Tijuana, Mexico, sex work is regulated by the municipal health department and includes regular testing for HIV and other sexually transmitted infections (STIs) for registered female sex workers (FSWs). However, Papanicolaou (Pap) testing is missing from current sexual health assessments. We aimed to answer the following research questions: (1) What is the prevalence of cervical abnormalities among a sample of FSWs in Tijuana, Mexico? (2) What are the correlates of cervical abnormalities among a sample of FSWs in Tijuana, Mexico? From 2013 to 2014, a cohort of 300 FSWs in Tijuana, Mexico were recruited using modified time–location sampling. Participants were given Pap, HIV, and STI tests. The prevalence of an abnormal Pap was 11.7% (35/300). FSWs ever registered with municipal health services were less likely to have an abnormal Pap result (4.8% versus 14.4%, p = 0.03), were more likely to report a previous Pap test (88.1% versus 70.4%, p = .001), and were more likely to report a sexual health checkup in the last year (60.7% versus 37.0%, p < 0.001) than those who had never been registered. FSWs, including those who registered with the municipality, remain at risk for cervical abnormalities.