The tax laws give preferential treatment to certain kinds of income and allow special deductions and credits for certain kinds of expenses. The alternative minimum tax attempts to ensure that anyone who benefits from these tax advantages pays at least a minimum amount of tax.

The alternative minimum tax is a separately figured tax that eliminates many deductions and credits, thus increasing tax liability for an individual who would otherwise pay less tax. The tentative minimum tax rates on ordinary income are percentages set by law. For capital gains, the capital gains rates for the regular tax are used.

You may have to pay the alternative minimum tax if your taxable income for regular tax purposes plus any adjustments and preference items that apply to you are more than the exemption amount. The exemption amounts are set by law for each filing status and listed in the Form 6251 Instructions.

For a child under age 14, special rules apply.

To find out if you may be subject to the alternative minimum tax, refer to the Form 1040 Instructions.

If you are liable for alternative minimum tax, you must complete Form 6251 (PDF), Alternative Minimum Tax-Individuals. If you are not liable for alternative minimum tax this year but you paid alternative minimum tax in one or more previous years, you may be eligible to take a special minimum tax credit against your regular tax this year. If eligible, you should complete and attach Form 8801 (PDF), Credit for Prior Year Minimum Tax-Individuals, Estates and Trusts.