Objectives To determine the contraceptive needs [including emergency contraception (EC)] of women seeking care from a publicly funded sexually transmitted infection (STI) clinic and to better understand women's knowledge of and attitudes towards EC. Methods An anonymous survey was administered to 197 women seeking services at one Chicago Department of Public Health STI clinic. Results After excluding women unlikely to become pregnant within the next year because of age, sexual orientation, hysterectomy and those who desired pregnancy ( n=47), data from 150 women were available for analysis. Thirteen percent were using “very effective” contraception (intrauterine contraception, implant or sterilization) and 26% were using “effective” contraception (contraceptive pill, patch, ring or injectable). Approximately 23% (95% CI 16.5–30.0%) may have benefited from immediate use of EC as they reported at least one act of unprotected intercourse within the past 5 days. Conclusion Many women seeking care from public STI clinics are at high risk of unintended pregnancy. A substantial number of women have an immediate need of EC at the time of their clinical visit. Efforts are needed to improve provision of EC as well as effective ongoing contraception for this population.