What is the process to apply for or renew an ITIN and required documentation?

1. The core step: fill out Form W‑7 and check the right box

Every official guide points to Form W‑7 as the central document: use it to request a new ITIN or to renew an expired one, and if renewing you must complete the renewal sections and mark the “renew an existing ITIN” reason on the form ^{[6] [7]}. The IRS instructs applicants to include the W‑7 with the supporting tax return unless an exception applies; for dependents or spouses you attach separate W‑7s to the front of the return ^{[1] [7]}.

2. Documents required: passports first, combinations allowed second

The IRS accepts a passport as a stand‑alone document proving both identity and foreign status; if you do not submit a passport you must submit a combination of two or more of the IRS’s 13 acceptable documents to meet identity and foreign‑status requirements ^{[2] [5]}. The IRS webpage on supporting documents lists specific requirements and cautions about translations, date limits for certain records (e.g., school or medical records), and procedures if you changed your name ^{[2] [7]}.

3. How to submit: mail, in‑person TAC, or Certified Acceptance Agent (CAA)

You may mail your W‑7 package to the IRS ITIN Operation in Austin, file in person at designated IRS Taxpayer Assistance Centers (TACs) that provide in‑person document review, or work with a CAA who can certify documents and forward the application—CAAs reduce the need to send original documents and are widely recommended by tax preparers ^{[1] [5] [4]}. Private commercial services and tax chains also advertise CAA help; H&R Block notes CAAs can submit copies and guide renewals at no extra charge in their offices ^[4].

4. Timing and what to expect after you file

The IRS asks applicants to allow about seven weeks for notification, extending to 9–11 weeks during tax season (January 15–April 30) or for overseas filings; independent trackers and tax advisers report a similar 7–11 week window and advise applying early ^{[1] [3] [8]}. The IRS issues CP565 to confirm an assigned ITIN or CP566 if more information is needed; third‑party guides emphasize FIFO processing but warn postal and peak‑season delays ^{[8] [1]}.

5. When to renew and consequences of not renewing

ITINs not used on a federal tax return for three consecutive tax years expire on December 31 after the third year of non‑use; the IRS will require renewal if an expired ITIN will be shown on a return ^{[9] [10]}. Tax filing with an expired ITIN will be processed but refundable credits tied to that ITIN may be disallowed until renewal, which can trigger notices and adjustments ^{[11] [12]}.

6. Practical options and tradeoffs: CAAs vs. mailing originals

Using a CAA avoids mailing original passports and often speeds acceptance of the package because CAAs certified copies are accepted; however, CAAs are third‑party services and may charge fees even though renewal itself is free to the taxpayer ^{[5] [4]}. Mailing originals is possible but carries risk and time; multiple nonprofit and government guides advise applicants to consider TAC or CAA options to keep originals local ^{[12] [5]}.

7. Conflicting claims and gaps in reporting

Most official and practitioner sources align on W‑7, supporting documents, submission routes, and 7–11 week processing ^{[6] [2] [3]}. Commercial sites sometimes claim shorter turnaround times or faster approvals when using their CAAs; these anecdotal timelines are variable and not confirmed by IRS guidance ^{[8] [13]}. Available sources do not mention any post‑2025 policy changes beyond standard PATH‑era renewal triggers; check the IRS pages cited above for updates before you apply ^{[7] [6]}.

Limitations: this summary relies only on the provided documents and links; for the definitive, up‑to‑date instructions and forms consult the IRS ITIN pages and W‑7 instructions cited ^{[1] [6]}.