1.1 million taxpayers didn’t file their taxes in 2007 and the IRS believes that there are about $1.1 billion in unclaimed tax refunds from that year. They are kind enough to mention it this year because this will be the last year in which you can file your 2007 tax return. The IRS gives you three years to file a tax return and you have until April 18th of 2011, since it’s the due date of your 2010 tax return, to file your 2007 tax return to see if you are due a refund. Half of those taxpayers are set to receive a refund of at least $640, which is much smaller than the average tax refund that year but still a sizable chunk of change.

To file a prior year’s tax return, you’ll need to talk to a tax professional or, to do it yourself, find that year’s forms. You can find the prior year’s forms at the IRS.gov website, where forms are archived as far back as 1980. Here is the full archive for all the 2007 tax forms.

Not sure if you filed a return that year? If you’ve been using a service, whether it’s software like TurboTax or an accountant, check with that service first. They will have record of your return if you filed with them. Otherwise, call the IRS at 1-800-829-1040 and ask them how you can look up your tax records with them.

How do I file a tax return for a deceased individual? If you are a surviving spouse or representative (of the taxpayer’s estate) of a deceased individual who may be entitled to a refund, but didn’t receive one because he or she didn’t file, you can file a return on their behalf. If you’re in this particular situation, it’s best you consult with a professional about the best course of action.

Finally, if you decide to file a 2007 return, you’ll also have to file a 2008, 2009, and 2010 return in order to receive your tax refund for 2007. By rule, you cannot receive a previous year’s refund if you didn’t file a tax return in subsequent years.

Jim writes about personal finance at Bargaineering.com.

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