General Tax Calendar
This tax calendar has the due dates for 2010 that most taxpayers will need. Employers and persons who pay excise taxes also should use the Employer's Tax Calendar and the Excise Tax Calendar.

Fiscal-year taxpayers. If you file your income tax return for a fiscal year rather than the calendar year, you must change some of the dates in this calendar. These changes are described under Fiscal-Year Taxpayers at the end of this calendar.

First Quarter
The first quarter of a calendar year is made up of January, February, and March.

Second Quarter
The second quarter of a calendar year is made up of April, May, and June.

Third Quarter
The third quarter of a calendar year is made up of July, August, and September.

Fourth Quarter
The fourth quarter of a calendar year is made up of October, November, and December.

Fiscal-Year Taxpayers
If you use a fiscal year (rather than the calendar year) as your tax year, you should change some of the dates in this calendar. Use the following general guidelines to make these changes.

The 3 months that make up each quarter of a fiscal year may be different from those of each calendar quarter, depending on when the fiscal year begins. Also see Saturday, Sunday, or legal holiday on
page 2.

Individuals
Form 1040. This form is due on the 15th day of the 4th month after the end of your tax year.

Estimated tax payments (Form 1040-ES). Payments are due on the 15th day of the 4th, 6th, and 9th months of your tax year and on the 15th day of the 1st month after your tax year ends.

Partnerships
Form 1065. This form is due on the 15th day of the 4th month after the end of the partnership's tax year. Provide each partner with a copy of Schedule K-1 (Form 1065) or a substitute Schedule K-1.

Form 1065-B (electing large partnerships). This form is due on the 15th day of the 4th month after the end of the partnership's tax year. Provide each partner with a copy of Schedule K-1 (Form 1065-B) or a substitute Schedule K-1 by the first March 15 following the close of the partnership's tax year.

Corporations and S Corporations
Form 1120 and Form 1120S (or Form 7004). These forms are due on the 15th day of the 3rd month after the end of the corporation's tax year. S corporations must provide each shareholder with a copy of Schedule K-1 (Form 1120S) or a substitute Schedule K-1.

Estimated tax payments. Payments are due on the 15th day of the 4th, 6th, 9th, and 12th months of the corporation's tax year.

Form 2553. This form is used to choose S corporation treatment. It is due no more than two months and 15 days after the beginning of the tax year the election is to take effect or at any time during the preceding tax year.