If you fill out your ISO exercise and hold information in the Wages and Income section of your return, TurboTax will automatically calculate AMT for you. Once you click that you held your exercise, it should ask if you received a form 3921 from your employer and you will then input your information (date option granted, date(s) exercised, exercise price per share, FMV per share on exercise date, and number of shares transferred). Turbo Tax will then calculate your additional income (FMV per share - exercise price per share x number of shares exercised). Once you continue on in your return, past wages and income and onto Other Tax Situations, it will show a calculation for AMT and let you know if you owe any or not. I agree, it's confusing when you click Other Tax Situations and they ask if you exercised ISOs, you click yes, and then none of the options are related to that; but then they don't tell you to go back and fill out that information in the Wages and Income section to get your AMT calculated.
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