You may pay all of your estimated tax by April 15th or in four equal amounts by the dates shown below.
| 1st payment . . . . . . . . April 15th * |
| 2nd payment . . . . . . . . June 15th * |
| 3rd payment . . . . . . . . September 15th * |
| 4th payment . . . . . . . . January 17th * † |
* If any due date falls on Saturday, Sunday, or a legal holiday, the installment is due on the next business day.
† You do not have to make the payment due January 15th, if you file your tax return by January 31 and pay the entire balance due with your return.
If, after March 31st, you have a large income, deductions, additional taxes, or credits that require you to start making estimated tax payments by using the annualized income installment method, the method is explained in IRS Pub. 505.