The IRS is completely separate from your state return and withholding. Or did the state send you a letter? The IRS may have adjusted your return or added an underpayment penalty. Check your 1040 line 38 for a penalty. It is possible for the IRS to recalculate it and send you a refund or a bill for more. If line 38 is blank you might have checked a box to let the IRS figure it for you.
