Currently, the U.S. Department of State (DOS) permits the addition of an additional 24 pages in you a U.S. passport which is valid and in good physical condition, however, as of January 1, 2016, the DOS will no longer accept applications for additional sets of pages to be added to the valid passports. Instead, U.S. passport holders must apply for a new passport. Note that the DOS began offering 52-page passports starting in October 1, 2014; presently passport applications may choose a 28-page or 52-page passport for the same cost. According to Department of State, "the decision to discontinue this service was made to enhance the security of the passport and to abide by international passport standards." Passport holders who wish to obtain an additional 24-page insert must file their applications prior to December 31, 2015.
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