On October 12, 1898 the city's mayor, Francisco Vega, received U.S. troops as part of the Spanish–American War. On that same day, for the first time in Vega Alta's history, the U.S. flag was lifted on city hall. From 1902 to 1905, Vega Alta became once more part of the neighboring municipality of Vega Baja. In 1905, the government of Puerto Rico passed a law, allowing Vega Alta to become a municipality with its own limits.
