Each year, the Alcoholic Beverage Regulation Administration (ABRA) issues a calendar of dates (PDF table) on which bars are allowed to stay open extra hours. This could be because of a holiday: on New Year’s Eve, regular on-premise licensees automatically got a reprieve to keep serving through 4 AM, though the extension is more often until 3 AM, like on Martin Luther King Jr. Day (January 16) or Washington’s Birthday (February 20). Even DC Emancipation Day (April 16) garners an extra hour at the pub.

The other reason for the closing hour reprieve is the ending of Daylight Savings Time, which occurs each autumn (this year on November 4). On that date, clocks “fall back” at 2 AM, meaning it’s suddenly 1 AM, meaning there’s an extra 60 minutes before standard closing hour. Of course, this comes with an accompanying loss of a bar hour in the spring; on March 11, 2012, 2 AM will all of a sudden become 3 AM, and any bars that are usually open until 3 AM will have to shut down what feels like an hour early.

But no worries, that’s the only shortening, most of the special dates are for extensions. Peep the list below and prepare to party.

 Photo via Flickr user Bill Spruce; link via David Smelson on Twitter