SBA Communications owns and leases space on wireless communications towers. SBA owns 46,328 towers across the U.S. and 12 international markets, primarily in South America, Central America, and Africa. The U.S. generates roughly 73% of site leasing revenue. T-Mobile, AT&T, and Verizon are the three largest customers. Wireless carriers pay rent to attach antennas and radio equipment to SBA's towers to run their mobile networks. SBA's business model is built on operating leverage: once a tower is built or acquired, adding a new tenant costs very little incrementally while generating recurring lease revenue. SBA averages 1.8 tenants per tower, leaving room for additional tenants. Organic growth comes from three sources: colocation (adding new tenants to existing towers), amendments (existing tenants upgrading equipment, such as adding 5G radios), and contractual rent escalators of roughly 2–3% annually on domestic leases. SBA also runs a small site development services business, helping carriers with permitting, construction, and antenna installation. SBA is structured as a REIT. Management focuses on AFFO per share as the primary financial metric. On capital allocation, SBA deploys cash toward tower acquisitions, new builds, buybacks, and dividends. The most recent major deal was the ~$1B acquisition of ~7,000 towers from Millicom in Central America. Key near-term headwinds include Sprint-related churn of ~$50M annually in 2025 and 2026 as T-Mobile consolidates its post-merger network.