There’s nothing worse than leading your daily life, ignorant of looming—then passing—deadlines that might affect your income and your standing with the IRS. You are busy making a living, raising the family, helping the community, then you get a letter in the mail saying that you owe a penalty to the IRS and possible prosecution. That will ruin your day, for sure.

Despite the wealth of information about when taxes are due, when tax returns need to be filed and when to pay the IRS if you it money, it can be easy to lose track of what needs to be done by when. In order to save you from any nasty letters that could induce a panic attack, here is some basic information that you will need in order to track the tax calendar year, a far more difficult process than simply ripping the pages off your calendar with each passing month. Let’s get started with basic terms:

• 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.
• Form 1040–This form is due on the 15th day of the 4th month after the end of your tax year. For instance, for the tax year 2011, Form 1040 is due on April 15, 2012.
• 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. In other words, using the above example, tax payments for 2011 would be due on April 15, 2011, June 15, 2011, September 15, 2011, and January 15, 2012.
• If you use a fiscal year rather than a calendar year as your tax year, you obviously need to change some of the dates in this calendar. The three 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. Many businesses, for instance, begin the fiscal year on July 1 of any given year, thus if you follow such a schedule for your tax payments, you must count July, August and September as the first quarter, October, November and December as the second quarter, etc. This would also mean that your Form 1040 is due on October 15 after the end of your tax year. Thus, your estimated payments using the above example would be October 15, December 15, and March 15 of the affected fiscal year, and July 15 after the fiscal year ended.

The vast majority of taxpayers use the calendar year to meet their tax deadlines and make their tax payments. Now that you have this handy guide to the tax calendar year, you should never be caught short with the IRS.