Background/Context: Student utilization of complex enrollment patterns has been identified as a significant recent development in higher education. Nearly a dozen different multi-institutional attendance patterns have been identified, including co-enrollment. Co-enrollment is simultaneous enrollment at two or more colleges or universities during the course of a given term or semester. Although research exists to understand the factors promoting persistence and degree completion for community college students, work does not properly account for co-enrollment or other forms of multi-institutional attendance. Purpose: The purpose of the study is to measure the impact of co-enrollment on success outcomes among a national sample of traditional age community college students. The following research questions are addressed: (a) In what ways are the characteristics of traditional aged community college students who co-enroll similar or different from students who do not co-enroll? (b) Does co-enrollment significantly increase or decrease the odds that a student will earn a degree and/or persist through the sixth year of college? Subjects: The sample was drawn from participants in the second follow-up of the Beginning Postsecondary Students Longitudinal Study (BPS: 04/09). The pre-matched sample was limited to the 4,920 students who began their postsecondary education at a two-year institution and were traditional in terms of age. The matched sample included a sub-sample of 700 co-enrollees and 700 matched students. Research Design: The study utilized a non-experimental quantitative design. Data Collection and Analysis: Propensity score matching techniques were used on observational data as a means of reducing observed selection bias. After the sample was shown to be balanced on observed covariates, logistic regression analyses were used to measures the influence of co-enrollment on the success of community college students. Results: Results demonstrate that, even after controlling for observable selection bias and variables previously shown to influence success outcomes for community college students, co-enrolling at more than one institution during a given semester significantly increases the odds that community college students will succeed. Conclusions/Recommendations: Co-enrollment may promote access to four-year institutions for community college students desiring to transfer and earn a four-year degree. State and federal policy makers and institutional leaders need to be aware that non-linear attendance is a legitimate way for students to experience and be successful in college. Descriptive work is needed to understand how and at what point students are attending multiple institutions.