A: For tax year 2000, nine states allow their taxpayers the option of deducting some percentage of their federal income taxes on their state income tax forms. The following table lists these states and the formula by which the deduction amount is calculated. Of these nine states, only three (Alabama, Iowa, and Louisiana) allow all taxpayers to deduct the full value of all federal personal income taxes paid. Three states (Missouri, Oregon, and Utah) allow all taxpayers to deduct a portion of federal income tax liability, and the remaining three states (Montana, North Dakota, and Oklahoma) allow this deduction only to certain taxpayers.
Although the calculation of the deduction amount differs between states, the deduction works the same way in all nine states: the amount to be deducted is simply subtracted from state taxable income. Thus, if an Iowa resident earning $100,000 a year pays $20,000 in federal income taxes, s/he can simply subtract $20,000 from taxable Iowa income. Since Iowa's top tax rate is 8.98 percent, the federal tax deduction results in a tax cut of $20,000 * 8.98= $1,796 on this taxpayer's Iowa return. Obviously, this deduction will result in a large revenue loss for states enacting it. So why do nine states allow it?
The most common rationale for this deduction is that it avoids double taxation. According to this argument, if a state includes federal income taxes paid in its own definition of taxable income, it is effectively "taxing a tax." In practice, however, the most important consequence of this deduction in states that allow it is a reduction in effective tax rates that is especially valuable for higher-income taxpayers. This is because the federal income tax is progressive. Taxpayers with lower incomes pay less in federal taxes than do people with higher incomes. Hence, lower-income families deduct much less than taxpayers at higher incomes. In addition, many low-income families don't pay any federal personal income tax and therefore have nothing to deduct. The net effect of this deduction, especially in states that allow a full deduction of federal income taxes paid, is to reduce the progressivity of state income taxes and to reduce the effective tax rates on wealthier taxpayers.
| States That Allow Deduction for Federal Income Taxes Paid | |
| Alabama | All federal personal income taxes paid are deductible. |
| Iowa | All federal personal income taxes paid are deductible. |
| Louisiana | All federal personal income taxes paid are deductible. |
| Missouri | Maximum federal income tax paid deduction is $5,000 |
| Montana | Taxpayers choose between taking the standard deduction and itemizing deductions. If they itemize, the full amount of federal taxes can be deducted UNLESS the taxpayer makes over $128,950. Then, the deductible amount is limited as income increases. |
| North Dakota | Taxpayers can either take the deduction for federal income taxes paid and apply higher state tax rates, or multiply their federal tax by 14% to get their state liability. 5% choose the deduction option. |
| Oklahoma | Taxpayers have two options, only one of which allows a deduction for federal income taxes paid. 58% of taxpayers choose the federal tax paid deduction option (which entails higher nominal state tax rates), and the rest forgo the federal deduction in favor of lower nominal state rates. |
| Oregon | Maximum federal income tax paid deduction is $3,000. |
| Utah | 50% of the federal income tax paid is deductible. |
Back to Frequently Asked Questions