Let's get this out of the way immediately:  

Do not believe the old husbands' tale that an extension increases your chance of an audit. No way.  Now let's look at why it's a good idea to file an extension.

1. No Time

If you are too busy to properly gather all records to file an accurate tax return, then since accuracy is the all-important element of tax preparation you must give yourself enough time to do it right. So, get an automatic six-month extension. You'll have until October 15, 2012 to file your tax return.

This extension of time to file, which must be filed or postmarked by the April 17 deadline, does not give you more time to pay any taxes due. If you have not paid at least 90% of your total tax by the April deadline you may also be subject to interest on the tax owed as well as a tax penalty.

You can obtain an extension, Form 4868, right here, or try one of the companies that offer free filing, info on that is at www.irs.gov/freefile.

Many states accept the federal extension. Some do not. Check for your state's requirements.

2. Lost Your Receipts

Or you lost other vital papers. Given some time you can do at least a partial reconstruction if you get in touch with your credit-card companies and banks and request copies of statements. Remember to also ask for the January 2012 statements. They very well may have December 2011 transactions on them.

3. Haven't Received Bank and Brokerage House 1099s

A lot of financial institutions, including banks and brokerage houses, have been granted permission to delay sending out their 1099s until March 15. These forms show all investment income, including interest, dividends, and stock sales as well as investment fees paid by you.

You may not have received yours yet. According to the Yahoo Finance website, the delays in 1099s are expected to lead to many more requests for extensions to file income taxes this year. You might consider being one of them.

Also, there have been many -- too many! -- changes to the reporting procedure for stock and other investment sales so if you sold expect corrected 1099s, who knows when?

4. Times Are Changing

2012 may be a transitional year when the economy turns around. Therefore you really should see how 2012 is shaping up before you make some decisions about your 2011 tax return. Circumstances unknown in April may come to light before October. You have flexibility in things such as pension contribution amounts, the method for depreciating a new car or office equipment, or changing an inventory method.

Talk with your tax professional about this. If in doubt about using a pro to prepare your return you might want to read my post Don't Do Your Own Tax Return.

5. Change. Change. Change.

Good golly have there been a lot. Not so much to the self-employed section of your tax return but to so much else. Tax pros have been given only months to reckon with, learn, absorb all these changes. A real understanding will come about to a considerable extent through on-the-job training. She'll be more experienced later this year when she has completed a goodly number of returns. To put it bluntly: let her learn the ropes on other people's tax returns.

For more info, please read my File an extension. It's the smart thing to do.

And a last note with the exception: Why you shouldn't delay filing your return.

1. Have No Money

If you don't have the money to pay the taxes you owe then by all means file your return by the deadline.

By filing on time you avoid late-filing penalties.

If at all possible pay something when you file. Every little bit you pay will avoid late payment interest and penalties.

There's a good chance -- 75% of taxpayers according to the IRS -- are eligible for an installment agreement for paying taxes owed. You can have your tax pro help you or apply using the web-based Online Payment Agreement application available at www.irs.gov. You can also contact the IRS at 800.829.1040 to discuss your payment options.