King’s actual birthday is Tuesday, Jan. 15 – he would have been 84 this year – but the official holiday is always celebrated on the third Monday of January. This year, that falls on Jan. 21.
It is also a postal holiday, which means there is no regular mail delivery/pickup or retail services on Jan. 21.
The Long Island Rail Road will operate on a Holiday Schedule. There will be 37 extra eastbound and westbound trains, to and from Penn Station, added on various branches to accommodate holiday travelers. Off-peak fares will also be in effect all day.