The U.S. Post Office prepared to handle an expected 23 million tax returns as last-minute filers rushed to get their 2007 income taxes in before midnight.

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Avoiding Income Tax Audits

A piece of IRS software called the Discriminant Inventory Function System analyzes tax returns for oddities and discrepancies. Based on a closely guarded formula, the system assigns each return a score that determines whether or not the IRS will audit you.

Here are some common red flags:

Obviously you can't avoid an income change if you get a better-paying job. And if you're self-employed, you're self-employed. But you can still do some things to decrease the likelihood you will be targeted for examination:

Keep Good Records: Three years is the statute of limitations on auditing returns that were filed on time. So, theoretically, the IRS could audit you for a return you filed three years ago. If you keep good records, you'll be able to answer any inquiries the IRS might have.

Explain Yourself: If your trip to the bowling alley is a justifiable business expense, include the receipts, a written explanation and any other appropriate documentation with your return. If you think the IRS might be curious, take care of it before they have a chance to ask you about it.

Just Because You Spent Money Doesn't Mean It's a Deduction: Don't go overboard with your deductions, especially if you're self-employed. Also, don't estimate your deductions -- use exact amounts based on receipts.

Beware of Tax Software: Tax software is great for returns at the simpler end of the spectrum. When you start getting into deductions and complex sources of income, consider verifying the accuracy of your return with a tax professional.

Compare: Compare your tax liability to the national average for your occupation. If there's a big difference between your tax liability and the rest of the country's, take another look at your return.

Be Tidy: A sloppy return is sure to get a thorough check by the IRS, especially if the all-important numbers are illegible.

Check and Recheck Your Return: Nip mathematical errors in the bud before you file.

There's no sure way to avoid an income tax audit. In fact, every year the IRS conducts a number of random audits to serve as benchmarks for its examinations. The best things you can do are file on time and pay what you owe. When it comes down to it, punctuality and accuracy are the only things the IRS really wants.

For more information on audits and tax returns, examine the links on the next page.