University counseling centers (UCCs) are tasked with delivering effective mental health interventions amidst increasing enrollment and declining resources. A growing number of UCCs have implemented session limits to meet demand with limited resources. To further understand the impact of this trend, we examined data obtained from a nationwide sample of 15,802 clients seeking treatment from 580 therapists at 32 UCCs utilizing the Behavioral Health Measure-20 (BHM-20). We compared psychotherapy outcomes to the number of clinical staff at UCCs utilizing either explicitly defined session limits or ambiguously defined session limits. There was a significant interaction between the way the sample of UCCs defined annual session limits, number of staff, and therapy outcomes. Specifically, higher therapy outcomes were observed at UCCs with explicitly defined session limits and fewer available staff. The ratio of enrolled students to clinical staff was not a predictor of outcome. Implications for clinical practice and agency session limits policy are discussed.