One of the big problems with the AMT, there’s no good answer to this common question. You can owe AMT liability due to any number of reason/s. Could be just one thing, could be a lot of little things. Some things that can contribute to an AMT liability are mundane items that appear on many tax returns. (See this list Top 10 Things that Cause AMT Liability.)

          If you use computer software to prepare your tax return, the program should (I would hope) be able to do the AMT calculations for you. If you’re preparing your return by hand, the only way to know for sure is to fill out IRS Form 6251 – a very laborious process, on that I charge almost $80.00 for, and that price is adjusted (usually up) almost every time.

         The best way to understand the alternative minimum tax liability is to see how it’s calculated. So, here’s what you do.