Here's a list of the top 10 alumni bases in the United States. 1 Indiana University | 805,000+ | Recently surpassed Penn State for the No. 1 spot. Covers graduates across nine in-state campuses. 2 | Penn State University | 802,000+ |Possesses one of the largest dues-paying, highly active alumni associations in the world. 3 | University of Michigan | 697,000+ |Widely considered one of the most geographically diverse and highly engaged networks globally. | 4 | University of California, Los Angeles (UCLA) | 670,000+ | Strongest presence on the West Coast, representing a massive professional and creative network in California. | | 5 | Ohio State University | 600,000 | Known for deep regional roots and a massive, fiercely loyal athletics fan base. | | 6 | University of Texas at Austin | 600,000 | Supported by the famous "Texas Exes" association, featuring over 150 global chapters. | | 7 | Purdue University | 600,000 | Massive footprint in engineering, aviation, and tech sectors globally. | | 8 | Texas A&M University | 593,000+ | Home of the "Aggie Network," famously known for having some of the highest alumni engagement and loyalty in the country. | | 9 | University of California, Berkeley | 580,000+ | A premier global research powerhouse with massive representation in Silicon Valley and academia. | | 10 | Michigan State University | 550,000+ | Boasts highly active local clubs across the country, particularly concentrated in the Midwest.