Getting an ITIN (Form W-7)
An ITIN is a taxpayer number for people who need to appear on a US return but cannot get a Social Security number — most often a foreign spouse or a child living abroad. It confers no immigration status and no work authorisation; it exists purely so the IRS can identify someone. For Korean families it is usually the blocker between a filed return and the filing status or credits they actually wanted.
Who this affects
- A US taxpayer with a foreign spouse who has no SSN
- Parents claiming a dependent child who is not SSN-eligible
- Non-residents who must file a US return for US-source income
- Anyone whose return was rejected for a missing or expired identification number
It is normally filed with a return, not before it
Form W-7 is usually submitted together with the tax return that needs the number, rather than as a standalone application in advance. Applying and filing are one package, which surprises people who expect to get the number first and file later.
Original documents are the sticking point
The IRS wants original identity documents or copies certified by the issuing agency. Mailing an original passport is the default path and people are rightly uneasy about it. Certified Acceptance Agents and some IRS Taxpayer Assistance Centers can verify documents so the passport does not leave your hands — worth seeking out.
ITINs expire
Numbers that go unused on a return for several consecutive years are deactivated, as were certain older number ranges. A return filed with an expired ITIN gets processed without the credits that depended on it, which reads as a mysterious refund reduction rather than an ID problem.
It is not an immigration document
An ITIN grants no status, no work authorisation and no benefits eligibility. It is issued precisely so that people who owe US tax can pay it regardless of status.
Common questions
Can my spouse in Korea get an ITIN?
Yes, if they need to be on your US return — for example to file jointly. The application goes with the return, and the documentation requirement is the same from abroad.
Do I have to mail my passport?
Not necessarily. A Certified Acceptance Agent can verify the document and forward certified copies, so the original stays with you. This is the usual reason to use one.
How long does it take?
Processing takes weeks and is slower in filing season. Because the ITIN and the return travel together, a slow ITIN delays the whole return — applying early in the year rather than in April is the practical fix.
Official sources
General information, not tax advice. Rules and thresholds change, and how they apply depends on your circumstances — confirm with a licensed professional before acting.