Each year, thousands of income tax refund checks are returned to the IRS as undeliverable because the taxpayer has moved, changed his or her name, or simply because the check has an incomplete or improper address. Although the IRS's website also has an interactive refund feature, the agency requires you to provide a refund amount and other information that makes it difficult to use for citizens who aren't sure whether they have a refund coming, or who can't remember how much it might be. As long as you have a refund to claim, then the NTU site directs you to the IRS toll-free number or the IRS website where you can securely claim your refund. Please visit the National Taxpayers Union Website here: http://www.ntu.org/main/components/irs04/