Estimating rates of public benefit use for lawful permanent residents (LPRs) is difficult given the limited availability of nationally representative data that disaggregate the foreign-born population by legal status. Using the 2008 Survey of Income and Program Participation—the only national survey that distinguishes LPRs from other non-citizens—we employ logistic regression to compare estimates of health insurance coverage for legal immigrants using two methods to infer legal status: (1) a logical approach and (2) a survey-based approach. The logical approach, relative to the survey approach, yields a higher predicted probability of having any insurance for LPRs (adjPP = 0.70) compared to the survey approach (adjPP = 0.57) and a higher likelihood of having public health insurance (adjPP = 0.26 compared to adjPP = 0.09, respectively). These findings suggest that the logical approach may overestimate lawful immigrants’ reliance on public benefits, which has implications for conclusions about recent changes to the public charge rule.