Objective To evaluate the effects of state insurance mandates requiring insurance plans to cover Pap tests, the standard screening for cervical cancer that is recommended for nearly all adult women. Data Sources Individual‐level data on 600,000 women age 19–64 from the CDC's Behavioral Risk Factor Surveillance System. Study Design Twenty‐four states adopted state mandates requiring private insurers in the state to cover Pap tests from 1988 to 2000. We performed a difference‐in‐differences analysis comparing within‐state changes in Pap test rates before and after adoption of a mandate, controlling for the associated changes in other states that did not adopt a mandate. Principal Findings Difference‐in‐differences estimates indicated that the Pap test mandates significantly increased past 2‐year cervical cancer screenings by 1.3 percentage points, with larger effects for Hispanic and non‐Hispanic white women. These effects are plausibly concentrated among insured women. Conclusions Mandating more generous insurance coverage for even inexpensive, routine services with already high utilization rates such as Pap tests can significantly further increase utilization.