The DS-4085 is the application form used to apply for additional visa pages for your US passport. This is a special government procedure to have a new set of pages sewn into your valid passport. Our guide will show you how to complete a passport application with all requirements for adding blank pages to a passport. You will need at least one blank page any time you enter a country, and if you need to get any visas, you will likely need to have at least two blank pages facing each other.