You cannot eFile a MO Tax Amendment anywhere, except mail it in. However, you can prepare it here on eFile.com.
Option 1: Sign into
your eFile.com account, modify your Return and download/print the
Form MO-1040 under
My Account. Check the "Amended Return" box, sign the form, and mail it to the address below.
Option 2: If you don't have an eFile.com account follow the step by step
instruction on how to prepare a tax return/amendment.
Option 3: If you want to do the math on your own paper return then complete, sign
Form MO-1040 - Print, Mail the Form to MO Tax Department to:
Receiving Refund Amendment Return:Missouri Department of Revenue
P.O. Box 500
Jefferson City, MO 65105-0500
Payment Attached Amendment Return:Missouri Department of Revenue
P.O. Box 329
Jefferson City, MO 65105-0329