ITIN credit claims and key lessons from TIGTA findings

When a client comes in with an individual taxpayer identification number (ITIN), either renewed or expired, or an amended return request tied to prior-year credits, slow down before you file. A March 27, 2026, Treasury Inspector General for Tax Administration (TIGTA) audit found the IRS allowed about $172.4 million in credits to ITIN holders who weren’t eligible, including cases where a Social Security number (SSN) was required, the ITIN was issued too late or the ITIN had expired.

The key issue isn’t whether the client has an ITIN today. It’s whether the identification number required for that credit was valid when the return was originally due. That’s where many of the problems in the TIGTA report started, and it’s why renewed ITINs deserve a closer review before you amend a return or sign off on a credit claim.

Quick ITIN credit-verification flow for tax pros

ITIN credit issues usually circle around the same few questions: What credit is being claimed, what year is at issue and was the identification number valid when the return was due? This is where TIGTA found most of the breakdowns. 

• Match the credit to the tax year before amending anything. 
• Confirm whether the credit requires an SSN or allows an ITIN. 
• Check the original due date of the return, including extensions. 
• Treat renewal status and expiration status as separate review points.
• Keep a due diligence file when required.

What to check before you file or amend

Start with the credit, not the client’s current status

Rules that worked in an earlier year may not work now. TIGTA notes the 2025 One Big Beautiful Bill Act (OBBBA) tightened identification rules for credits tied to ITINs, including the child tax credit (CTC), additional child tax credit (ACTC) and American opportunity tax credit (AOTC). NATP’s Feb. 1, 2026, TAXPRO article also emphasizes that these rules now focus on whether the SSN is valid for employment and issued by the due date of the return.

Check the date that controls the claim

TIGTA’s findings turned on timing. The report identified 1,488 returns where the IRS allowed refundable credits even though the ITIN was not issued on or before the return due date. It also identified 43,604 returns where the IRS allowed about $138.8 million in refundable credits even though the ITIN had expired before the tax return due date.

Treat a renewed ITIN as a follow-up question, not the answer

This is the real trap. TIGTA says the IRS still follows Notice 2016-48, which treats the issuance date of a renewed ITIN as the original issuance date, not the renewal date. 

That means a taxpayer may appear eligible for prior-year credits even if the ITIN was expired when the return was due. TIGTA said revising that guidance could have prevented $138.8 million in improper refundable credit payments and concluded the current approach appears inconsistent with the PATH Act’s language and intent.

Document the file like it may be reviewed later

If a return involves a credit tied to identification rules, keep the dates, extension records, renewal history and credit-specific support in one place. Preparers must now verify, document and track identification status with significantly more rigor; front-end IRS checks leave little room for assumptions.

Why these ITIN program findings matter now

There are two reasons this issue is bigger than one audit. 

• First, TIGTA says the IRS’s ITIN process is still heavily manual, and Form W-7, Application for IRS Individual Taxpayer Identification Number, can still take seven to 11 weeks to process. 
• Second, the IRS and TIGTA still disagree on how renewed ITINs should be treated for retroactive credit claims. That makes this a live practice issue, not just a historical cleanup problem.

For tax pros, the safest approach is simple: don’t let a current ITIN status answer a prior-year credit question. Check the credit, check the date and check the documentation before you promise a result.

For more guidance, explore these related NATP webinars:

• The Role of ITINs in the U.S. Tax Filing System On-Demand Webinar
  Best for tax pros who want a deeper look at ITIN rules and filing-system basics. 
• Inside OBBBA - Why Getting SSNs Right Just Got Critical On-Demand Webinar, also available in Spanish
  Best for tax pros who want more detail on how OBBBA tightened identification rules and why SSN accuracy now matters more at filing. 
• Filing Amended Returns for Individual Taxpayers On-Demand Webinar
  Best for tax pros who want practical guidance on amended return decisions, documentation and risk points tied to prior-year claims.