The IRS reported on May 19 that the tax filing date for 2016 will be April 18; except if a taxpayer resides in Maine or Massachusetts, then it will be April 19. Next year, April 15 will be on a Friday, which is also a holiday observed in Washington D.C. for Emancipation Day. Since tax days cannot conflict with holidays or occur on a weekend, the date is set for Monday, April 18, 2016.
However, since Monday, April 18 is a holiday (Patriots’ Day) in Maine and Massachusetts, the tax filing date for those two states will be Tuesday, April 19, 2016.