Form W-7 is the IRS application for an Individual Taxpayer Identification Number. One page long, deceptively simple, and responsible for an enormous number of rejected applications every year. This guide walks through what the form asks, what trips people up, and how the document rules actually work.
What Form W-7 is used for
The W-7 does one job: it asks the IRS to issue you an ITIN, or to renew one you already have. It is almost never filed alone. In most cases the form must be attached to the federal tax return that creates your need for the number, and the return is filed on paper with the W-7 on top. A W-7 sent without a return, when no exception applies, comes straight back.
Who fills out a W-7
Anyone who needs an ITIN: the applicant, or a parent or guardian applying for a child, or a representative preparing it on the applicant's behalf. One form per person, so a family filing together submits one W-7 for each spouse or dependent who needs a number, each with its own documents. This is where the CAA appointment earns its keep for families: every application handled in one sitting instead of one fragile mail package.
What the form asks, and where people go wrong
The W-7 asks why you need an ITIN (the reason checkboxes at the top), your name exactly as your documents show it, your mailing and foreign addresses, birth information, and the identity documents you are submitting. The classic rejection triggers, in the order we see them: a reason box that does not match the attached return, a name that does not exactly match the passport, a missing or unsigned return, documents that are copies rather than originals or agency certified copies, and applications for people who are actually SSN eligible. None of these are complicated. All of them restart a two month clock.
The document problem, and how a CAA solves it
The IRS wants proof of identity and foreign status, and it wants originals or copies certified by the issuing agency. Notarized copies do not count. For most applicants that means mailing a passport to the IRS and living without it for two months or more, or finding an alternative. The alternative is a Certified Acceptance Agent: authorized by the IRS to verify your original documents in person and certify the application, so your passport stays with you. Our founder is a CAA, and document verification happens in one appointment at our office. Details on our ITIN application service.
After you file
A complete, correct application typically comes back with an ITIN assignment letter in roughly seven weeks, longer in filing season. Keep the letter. If the IRS needs more information it writes to you, and the response deadline matters. If the application is rejected, the notice says why, and most rejections are fixable on a properly prepared resubmission. We diagnose and refile rejected applications regularly, usually through the CAA process the application should have used the first time.