N.Y. Election Law § 11-110
* 1. To be counted, any ballot cast under the provisions of this article must be received by the appropriate board of elections not later than the close of the polls on election day except that all ballots contained in envelopes showing a cancellation mark of the United States postal service, or a foreign country's postal service with a date which is ascertained to be not later than the day of the election, shall be cast and counted if received by the board of elections not later than seven days following the day of election. * NB Effective until December 31, 2020 * 1. To be counted, any ballot cast under the provisions of this article must be received by the appropriate board of elections not later than the close of the polls on election day except that all ballots contained in envelopes showing a cancellation mark of the United States postal service, or a foreign country's postal service with a date which is ascertained to be not later than the day before election, shall be cast and counted if received by the board of elections not later than seven days following the day of election. * NB Effective December 31, 2020