Martin Luther King Jr. Day ( MLK Day )—which is Monday, January 19, 2026—is a federal holiday that’s recognized across the United States, meaning it’s likely to affect several public services, including banks , mail, and deliveries. MLK Day was first officially observed on January 20, 1986, after President Ronald Reagan signed the holiday into law in 1983, as documented by the National Museum of African American History & Culture. Like with other federal holidays, several government services—