On March 29, 1900, Pateros was made a Municipality by virtue of General Order No. 40. Act. No. 137 of the Philippine Commission promulgated on June 11, 1901 incorporated Pateros with newly created province of Rizal. Two years later (October 12, 1903), Act. No. 942 consolidated Pateros, Tagig and Muntinlupa for purposes of economy and centralization, with Pateros as the seat of Municipal government. On March 22, 1905, the "Municipality of Pateros" was changed to "Municipality of Tagig". Later, Executive Order No. 20 dated February 29, 1908 separated Pateros from Tagig. Pateros regained its independent status as a Municipality on January 1, 1909 by virtue of Executive Order No. 36. On November 7, 1975, Pateros became part of the Metropolitan Manila through Presidential Decree No. 924.