The refund checks, averaging about $953, can be claimed as soon as taxpayers update their addresses with the IRS. Some taxpayers have more than one check waiting, the tax authority has revealed.

“Taxpayers should not miss out on getting their money back,” announced Richard Morgante, Commissioner of the IRS Wage and Investment Division, adding:

”The IRS makes it as easy as possible for taxpayers to update their addresses and claim their refunds.”

The 'Where’s My Refund?' tool on IRS.gov enables taxpayers to check the status of their refunds. A taxpayer must submit his or her social security number, filing status, and amount of refund shown on their 2006 return. The tool will provide the status of their refund, and in some cases provide instructions on how to resolve delivery problems.

The number of undeliverable refunds each year is a relatively small portion of all refunds returned to taxpayers. So far in 2007, the IRS has processed nearly 105 million refunds, totaling about $240 billion, either by mail or direct deposit.

In fact, undeliverable refunds account for less than one-tenth of one percent of all refunds, or about one in a thousand.

A refund check is normally returned as undeliverable when a taxpayer moves without updating his or her address with either the US Postal Service or the IRS.

The list of taxpayers due undeliverable refunds this year rose about 21% from 95,746 last year. The sharp increase is due in part to the Telephone Excise Tax Refund. The refund is a one-time payment available on 2006 federal income tax returns. It was designed to return to taxpayers previously collected long-distance telephone taxes. Individuals, businesses and tax-exempt organizations are eligible to request it.

Refund checks are mailed to a taxpayer’s last known address. Checks are returned to the IRS if a taxpayer moves without notifying the IRS or the US Postal Service.