The deadline for all nominating ballots to be received by the Hugo administrator is Monday 31 March 2014, 11.59 pm PDT (7.59 am BST on Tuesday 1 April – UK time).
Members of Loncon 3 who have an Attending, Young Adult Attending or Supporting membership by 31 January 2014 are eligible to nominate for the Hugo Awards and the Retro-Hugos. Equivalent members of LoneStarCon 3 (the 2013 Worldcon) and Sasquan (the 2015 Worldcon) at that date are also eligible to nominate.
More details can be found here: http://www.loncon3.org/nominations.php