The Alternative Minimum Tax credit is a way of recouping money you were forced to pay as Alternative Minimum Tax (AMT) in a prior year. You can only take advantage of this credit in a year in which you dont have to pay AMT. In addition, you cant use the credit to reduce your AMT liability in the future. However, you can carry over any unused portion of the credit to future years.
Use Form 8801 to figure the Alternative Minimum Tax credit, as well as any amount you can carry over to future years.
You should file Form 8801 if you had:
An AMT liability for other than an exclusionary item, as opposed to a "timing issue item" or deferral item. Examples of deferral items are depreciation or ESOPs exercised and not sold.
An Alternative Minimum Tax credit amount to carry forward
An unallowed nonconventional source fuel credit or qualified electric vehicle credit
For more information, see the Form 8801 instructions.