Returns to education in professional football

After three years in college, football players face a trade-off between spending more time in college and pursuing a career in the National Football League (NFL). We analyze the salaries for rookies in the NFL and instrument the endogenous decision to enter the professional market with the month of birth (relative age effect). A player enjoys a 6 percent higher starting salary in the NFL for each additional year with the college team. The returns to education in professional sports are sizable and similar to returns to formal education.