Background: Homeless persons depend disproportionately on the health-care safety net for medical services. National reports identify financial strains to this safety net. Whether this has affected homeless persons is unknown. Objectives: We quantified changes in the proportion of homeless persons reporting unmet need for health care in Birmingham, Alabama, comparing two periods, 1995 and 2005. We assessed whether a period effect was independent of characteristics of persons surveyed. Design: Analysis of two surveys conducted with identical methods among representative samples of homeless persons in 1995 (n∈=∈161) and 2005 (n∈=∈161). Measurements: Report of unmet need (inability to obtain care when needed) was the dependent variable. Two survey periods (1995 and 2005) were compared, with multivariable adjustment for sociodemographic and health characteristics. Reasons for unmet need were determined among the subset of persons reporting unmet need. Results: Unmet need for health care was more common in 2005 (54%) than in 1995 (32%) (p∈<∈0.0001), especially for non-Blacks (64%) and females (65%). Adjusting for individual characteristics, a survey year of 2005 independently predicted unmet need (odds ratio 2.68, 95% CI 1.49-4.83). Among persons reporting unmet need (87 of 161 in 2005; 52 of 161 in 1995), financial barriers were more commonly cited in 2005 (67% of 87) than in 1995 (42% of 52) (p∈=∈0.01). Conclusion: A rise in unmet health-care needs was reported among Birmingham's homeless from 1995 to 2005. This period effect was independent of population characteristics and may implicate a local safety net inadequacy. Additional data are needed to determine if this represents a national trend. © 2009 Society of General Internal Medicine.