N.Y. ELN Law § 11-212

§ 11-212. Special federal ballots; deadline for receipt. All special\nfederal ballots received by the board of elections before the close of\nthe polls on election day shall be retained by the board of elections\nand cast and canvassed pursuant to section 9-209 of this chapter. All\nballots contained in envelopes showing a cancellation mark of the United\nStates postal service or a foreign country's postal service, or showing\na dated endorsement of receipt by another agency of the United States\ngovernment, with a date which is ascertained to be not later than the\nday of the election, shall be cast and counted if received by the board\nof elections not later than seven days following the day of a primary\nelection or thirteen days following the day of a general or special\nelection except that the special federal ballot of a voter who requested\nsuch ballot by letter, rather than application, shall not be counted\nunless a valid application form, signed by such voter, is received by\nthe board of elections with such ballot. All ballots received by the\nboard of elections and all federal write-in ballots received from\nspecial federal voters not later than seven days following the day of a\nprimary election or thirteen days following the day of a general or\nspecial election, shall be retained at the board and shall be cast and\ncanvassed in the same manner as other ballots retained by such board.\n