According to the IRS, the economic stimulus payment that more than 124 million households will have received "will not be taxable, and it won't reduce your 2007 or 2008 refund or increase the amount you owe when you file your 2008 return."
In fact, according to the IRS the following are the possible scenarios that taxpayers may encounter when filing their 2008 tax return as shown below;
1. If a taxpayer received all of the allowed rebate in your 2008 rebate check, there will be no affect to your 2008 tax return.
2. If a taxpayer received more rebate than the allowed rebate when filing your 2008 tax return, there will be no affect.
3. If a taxpayer received less rebate than the allowed rebate when filing your 2008 tax return, you will be eligible for the rebate credit of the difference.
Thus, as far as your situation is concerned, your tax refund will not be affected.