April 17, 2018
Tax return due. Your 2017 income tax return is due, unless you file for an extension until Oct. 15.
File for extension. If you want an automatic extension of time to file your 2016 tax return, file Form 4868. Filing the form gives you until Oct. 15 to file your return. To avoid a penalty, however, be sure to pay any tax that was due on April 17.
Individual Retirement Accounts or Roth IRAs. This is the deadline for making contributions to IRAs or Roth IRAs for tax year 2016.
Estimated tax payment. Your first-quarter estimated tax payment for 2018 is due.
State tax returns. If you are required to file a state tax return, it is probably due — but check with your state to be certain. Many states automatically extend the filing time for those who have filed for a federal extension.
Household employers. If you paid cash wages of $1,800 or more in 2016 to a household employee, file Schedule H (Form 1040) with your income tax return and report any employment taxes by April 18.
June 15, 2018
Filing deadline. If you’re a U.S. citizen or resident alien living and working (or on military duty) outside the U.S. and Puerto Rico, file Form 1040 and pay any tax, interest and penalties due. You can file for an extension until Oct. 15.
Estimated taxes due. Your second-quarter estimated tax payment (using Form 1040-ES) for 2018 is due.
Sept. 15, 2018
Estimated tax due. Your third-quarter estimated tax payment (using Form 1040-ES) for 2018 is due.
All Corporation (Forms 1120 & 1120S), Partnerships (Form 1065), and Trusts (Form 1041) are due by this date.
Oct. 15, 2018
Income tax return due. Your 2017 income tax return is due if you filed an extension request using Form 4868.
Dec. 31, 2018
Deduction deadline. The last date to make payments that can be deducted from your 2018 return.
Keogh plan deadline. The last date to establish a Keogh plan so you can deduct a Keogh plan contribution on your 2018 return.