If you have a tax underpayment lurking in your books, it’s going to cost you more. Of course, that means if you make an overpayment, you’ll be getting more back from the feds too. Starting Oct. 1, the interest rates for 4Q ‘08 are:
• 6% for underpayments
• 8% for large corporate underpayments
• 5% for corporate overpayments, and
• 3.5% for the portion of a corporate overpayment that’s more than $10,000.

Tags: Interest rates, IRS, Tax compliance