I am applying for an ITIN for my wife and we have got all the documents ready to mail to the IRS, but I just realized that the state return is mailed to a different address and I also know that the State's Department of Revenue would not process my tax return without a SSN or ITIN. Can I attach form W-7 to my state return and write ITIN TO BE REQUESTED or do I have to fill out form 4868 to apply for an extension, even though I am ready to mail my federal tax return right now? My state of residence is California.
