This page provides a list of items that can cause (or contribute to) liability under the alternative minimum tax. The list isn’t complete — there are other items that can contribute to AMT liability. Based on our experience, the items described below are likely to affect more people than other items.

1. Exemptions
   Believe it or not, exemptions contribute to AMT liability. The exemptions you claim for yourself, your spouse and your dependents are not allowed when calculating alternative minimum tax. It’s pretty rare (though not impossible) to see a tax return where someone had to pay AMT solely because of their exemptions, but the more exemptions you claim, the more likely it is that you’ll have AMT liability when all is said and done.
2. Standard Deduction
   Some 70% of American taxpayers claim the standard deduction (rather than itemizing). The standard deduction isn’t allowed under the AMT. Usually this isn’t a problem because the AMT generally hits people with higher incomes, and these people are more likely to claim itemized deductions. Yet it’s worth noting that a deduction that’s so widely used can contribute to AMT liability.
3. State and Local Taxes
   If you itemize, there’s a good chance you claim a deduction for state and local tax, including property tax and state income tax. For 2004 and 2005, you can claim a deduction for sales tax if you don’t claim a deduction for state or local income tax. These deductions are not allowed under the AMT. If you live in a place where state and local taxes are high, you’re more likely to be subject to the alternative minimum tax.
4. Interest on Second Mortgages
5. Medical Expenses
6. Miscellaneous Itemized Deductions
7. Various Credits
8. Incentive Stock Options
9. Long-Term Capital Gains
10. Tax-Exempt Interest
11. Tax Shelters

This list has been severely abridged. To read the full list and full descriptions, view the original post at it’s source:

Top Ten Things that Cause AMT Liability (Fairmark)