Internal promotions remain the dominant path to the top of America’s largest companies. As of June 30, 2025, nearly 60% of S&P 500 C-suite leaders were appointed from inside their own organizations, reinforcing the enduring value of leadership development and disciplined succession planning.That internal bias is even stronger at the very top, according to a Spencer Stuart report. Seventy-six percent of CEOs and 80% of chief operating officers (often a stepping stone to the corner office) were promoted from within their companies, making these roles the most likely to be filled by insiders.Company scale plays a meaningful role in these outcomes. Larger organizations, particularly those with multiple business units, tend to generate deeper internal talent benches. More functional leadership roles allow high-potential executives to be developed, tested, and rotated across the enterprise, increasing the odds that boards can look inward when critical roles open.External hiring still remains a vital lever, especially when companies need to strengthen capabilities in highly specialized areas such as technology, but it is typically used selectively rather than as the default.Industry dynamics also shape internal promotion rates. In the industrial and consumer sectors, 61% and 62% of C-suite leaders, respectively, were internal appointments. Healthcare and technology trail with 56 percent—the lowest share of insiders among major sectors. Even when companies recruit externally, expectations differ by role. For CEOs and COOs, industry experience remains a strong prerequisite, with fewer than 20% of external hires coming from outside the company’s sector.Taken together, the data suggest that building a long runway inside an organization, gaining breadth across functions and business units, and developing a track record of industry expertise continue to outweigh external visibility alone when boards make their most consequential decision for the top job.Check out the 2026 most powerful rising executives in the Fortune 500Next to Lead will be off for the holidays and back in your inbox on Jan. 5.Ruth Umohruth.umoh@fortune.comThis story was originally featured on Fortune.com