If you've safely determined that you need to file an amended return, let's take a look at some deadlines for submitting it. First, as we discussed earlier, tax experts usually advise paying what you owe to the IRS as soon as possible to avoid a higher interest payment. However, if you want a refund from the IRS, you'll need to get the 1040X in by the deadline.
Although amended returns can be submitted immediately after the original, if you are amending to ask for a bigger refund, the IRS asks that you wait until you have received your first refund check before filing a 1040X. Generally, in order to receive an adjusted refund or a credit, you must submit the 1040X within three years of the date you filed the original return or two years after you paid the tax (whichever is later).
The IRS doesn't punish those who filed early, however: If you filed the original before April 15, the IRS still considers it filed on April 15 for the purposes of this deadline. On the other hand, if you had an extension, the return is considered filed on the extension due date, regardless of whether you filed it earlier. For those who struggle to take care of their taxes because of physical or mental disabilities, the IRS can make exceptions.
You do have more time to file for a refund under certain circumstances. For instance, if you held a security (such as corporate stock or bond) that became worthless, or a business owed you money that it couldn't pay back (bad debt), you generally have seven years from the due date of the return in the tax year in which the security or debt became worthless. Or, if you need to change a deduction for foreign taxes or foreign tax credit, the IRS allows 10 years from the due date of the return for the year the taxes were paid (not including extensions). Check the form instructions for more special situations.