[header] How to amend a federal tax return [title] Check the limitations. [step] When you find that you need to amend a tax return, you need to make sure the statute of limitations on filing one hasn't run out. The statute of limitations, or time allowed for the action, on getting a refund from an amended tax return is three years. 
That means if you're filing an amended tax return because you're hoping to get an additional refund, the cutoff time is three years after the original return was filed. Wait longer than that and you won't get a refund.