How many years back can you put in an amended return?

You can generally file an amended tax return up to three years back from the original filing deadline, including extensions. If you are claiming a refund, you must file the amended return within this three-year window. However, if you are amending due to a bad debt or worthless security, you may have a longer period of up to seven years. Always check the latest IRS guidelines or consult a tax professional for specific situations.