OBBBA's New CTC Rule: The MFJ Spouse-SSN Check Preparers Can't Skip

A married couple sits down with you. One spouse has an SSN, the other has an ITIN, and the children have valid SSNs. Last year, your Child Tax Credit review probably centered on the children.

For tax year 2025 returns filed in 2026, that is no longer enough.

The One Big Beautiful Bill Act changed the CTC and Additional Child Tax Credit identification-number rules for Married Filing Jointly returns. Form 8867 was updated for the change, and the paid-preparer due-diligence penalty is $650 per failure for returns and refunds filed in 2026.

This is not a software trivia issue. It is an intake and workpaper issue.

What changed for MFJ returns claiming CTC

For a 2025 MFJ return claiming CTC or ACTC, your file needs to show the ID-number facts for both spouses, not only the primary taxpayer.

At a practical level, the review is:

• The qualifying child still needs a valid SSN for CTC or ACTC.
• On an MFJ return, at least one spouse must have a valid SSN.
• The other spouse must have either an SSN or an ITIN, issued on or before the due date of the return.
• A two-ITIN MFJ couple should be flagged before the CTC or ACTC line is ever prepared.

The operational change is small, but easy to miss. If your intake asks detailed ID questions for the primary taxpayer and dependents but treats the spouse as basic demographic data, your old workflow has a blind spot.

The two files that create risk

The first risky file is obvious: two spouses with ITINs, children with SSNs, and a CTC claim that should have been stopped.

The second file is quieter: one spouse with an SSN, one spouse with an ITIN, and the CTC claim is allowed, but your workpapers do not show how the spouse-SSN check was made.

That second file is where good preparers get surprised. A correct return can still leave you exposed if the file does not show that you asked, reviewed, and documented the facts Form 8867 depends on.

What to add to intake now

For every MFJ engagement where CTC or ACTC may be claimed, add a required spouse-identification block:

• Taxpayer: SSN, ITIN, or neither
• Spouse: SSN, ITIN, or neither
• If SSN or ITIN: was it issued on or before the return due date?
• What did the preparer rely on: client document, prior-year file, portal upload, or a dated preparer note?

This does not need to feel scary to the client. In plain English: the rule changed, and your office now has to document both spouses before claiming the credit.

If you send a pre-appointment checklist, add the spouse ID item there too. The bilingual document checklist is a natural place to make this visible before the client walks in.

What Form 8867 workpapers should show

Do not rely on memory. Your workpapers should make the review easy to reconstruct later.

A defensible file might include:

• A structured intake response for each spouse, timestamped in your portal.
• A copy of any client document relied on, or a dated note describing what was reviewed.
• A reviewer note that the MFJ spouse-SSN rule was checked before signing Form 8867.
• A clear stop flag when both spouses use ITINs and the return is trying to claim CTC or ACTC.

The point is not to create paperwork for its own sake. The point is to make the answer obvious when someone opens the file two years from now.

The $650 reason to fix it before next season

For returns and refunds filed in 2026, the due-diligence penalty under IRC 6695(g) is $650 per failure. Ten MFJ-with-CTC files with a missing spouse-SSN check can become $6,500 of exposure before you even talk about EITC, AOTC, or Head of Household.

Small offices feel that kind of penalty. They also feel the lost time: finding old files, explaining notes, and retraining staff during an IRS review.

Three workflow fixes

Add a hard-stop field. MFJ returns should not move to prep until both spouses' SSN/ITIN status is complete.

Update the 8867 review step. Before signing, confirm the spouse-ID rule and the child-SSN rule are both documented.

Refresh repeat-client files. Do not assume last year's intake answers cover this year's rule. Ask again for tax year 2025.

This is the kind of compliance change Intaxion is built for: a small bilingual intake question, captured once, tied to the return, and visible before the file reaches review.