San Ildefonso is a municipality in the province of Bulacan, Philippines. According to the 2010 census, it has a population of 95,000 inhabitants.With the continuous expansion of Metro Manila, the municipality is now part of Manila's built up area which makes San Ildefonso it's northernmost part.July 23, 2013, An entertainment and supermarket complex was opened where the old public market used to stand. This made San Ildefonso the "Biglang bukas, Ubos agad" of Bulacan.