Entering Partnership AMT Basis in TurboTax

Skip to “Conclusion” for answer.

The very last column of my 2010 UNG sale schedule is labeled “Alternative Minimum Tax Basis Adjustment”.  The only entry there is 0, so I didn’t pay any attention to it.  It seems however I must in the future, because MLPs often are dual-basis (one basis for regular tax and another for AMT), and I’m interested in investing in MLPs.

Looking over the schedule again, I learned this AMT adjustment was for line 17 of Form 6251.  I decided to start an experiment to find out where in TurboTax to enter that adjustment.

First thing I learned is that TurboTax actually uses two separate Schedules D, one for regular tax, and the other for AMT.  (To see the AMT Schedule D, click on “Schedule D AMT” in Forms view.)  However, in my experiment the two Schedules D had identical entries.

Wanting to play with the cost basis, I went back to the sale price screen of K-1 “step-by-step” interview.  And there was the answer!  On that screen one can enter a basis for regular tax and another for AMT.  When I made the AMT basis different from regular basis, the difference showed up on Form 6251, Line 17, by way of AMT Schedule D.

Conclusion

To use AMT basis adjustment (for example, Column 9 of 2010 UNG K-1), add the adjustment to regular-tax basis to get AMT basis, and enter both on the sale price screen during K-1 “step-by-step” interview.