Where do I mail form 3531 My son received a form 3531 attached to his tax return stating that he forgot to sign his 1040 tax return. He signed it but we lost the return envelope that was sent to us and we do not know where to send it. I have tried calling the IRS but was put on hold for ever after navigating through a maze of voice options. I'm sure this is a simple question but cannot find the answer anywhere. |