Family ties vs. tax law: Montes Gonzalez v. Commissioner

Few areas of tax law are as personal or as fraught with frustration as claiming a child-related tax credit. The child tax credit (CTC) is intended to provide meaningful support to families, but the statutory requirements for eligibility are technical and strictly enforced. 

The recent decision in Montes Gonzalez v. Commissioner, T.C. Memo. 2025-132, underscores just how unforgiving these rules can be, especially when it comes to the substantiation of a child’s residency.

The child tax credit and qualifying child rules

The child tax credit under §24 is one of the most significant tax benefits available to families with children. However, to claim the CTC, a taxpayer must establish that the child meets the definition of a “qualifying child” under §152(c). The qualifying child rules are not merely formalities; they are strictly construed and rigorously enforced by the IRS and the courts. 

Under §152(c), a qualifying child must satisfy five requirements:

1. Relationship: The child must be the taxpayer’s son, daughter, stepchild, foster child, brother, sister, stepbrother, stepsister or a descendant of any of them.
2. Age: The child must be under age 19 at the end of the year, or under age 24 if a full-time student, or any age if permanently and totally disabled. For CTC purposes, the qualifying child must also be under age 17 at the end of the tax year.
3. Residency: The child must have lived with the taxpayer for more than half of the tax year, measured by the child’s principal place of abode, subject to limited temporary-absence exceptions.
4. Support: The child must not have provided more than half of their own support for the year.
5. Joint return: The child must not file a joint return for the year, unless it is only to claim a refund.

Montes Gonzalez v. Commissioner: facts and dispute

In Montes Gonzalez, a married couple claimed the child tax credit and related benefits for the couple’s nephew. The IRS disallowed the credits, and the dispute proceeded to the U.S. Tax Court. By the time of trial, the only issue left for the court to decide was whether the nephew qualified as a “qualifying child” under §152(c).

The IRS conceded all §152(c) elements except residency.  The sole point of contention was the residency requirement: Did the nephew live with the taxpayers in the same principal place of abode for more than one-half of the tax year, as required by §152(c)(1)(B)?

The residency requirement is a strict standard

The residency requirement is often the most challenging element for taxpayers to substantiate. The law requires that the child have the “same principal place of abode as the taxpayer for more than one-half of such taxable year.” This is not a mere technicality; it is a factual determination that must be supported by credible evidence.

The IRS and the courts look for objective documentation to establish residency. Acceptable forms of proof include school records, medical records, official correspondence, or other documents that show the child’s address and the period of residence. Testimony alone, especially if uncorroborated, is rarely sufficient.

In Montes Gonzalez, the taxpayers were unable to provide sufficient documentation or credible testimony to establish that the nephew resided with them for the requisite period. The court found that, despite the undisputed familial relationship and the taxpayers’ genuine intentions, the lack of substantiating evidence was fatal to their claim.

Documentation is essential

Montes Gonzalez serves as a cautionary tale for taxpayers and practitioners alike. Even when the familial relationship is undisputed and the taxpayers’ intentions are genuine, failure to meet the technical substantiation requirements will result in denial of the credit. The case highlights the importance of maintaining thorough records such as school records, medical records or other official documents that can corroborate a child’s residence.

The IRS provides guidance on the types of documents that can be used to establish residency, including:

• School or daycare records
• Medical or health records
• Social service records
• Official letters or statements from landlords, property managers or government agencies

Taxpayers should ensure that such records clearly show the child’s name, the address and the relevant date(s). Inconsistent or incomplete documentation can undermine a claim, even if the underlying facts are sympathetic.

Takeaways for taxpayers and practitioners    

• The qualifying child rules under §152(c) are strictly applied, and the residency requirement is often the most challenging to substantiate.
• Taxpayers bear the burden of proof and must be prepared to provide documentary evidence of a child’s residence for more than half the year.
• Good intentions and close family ties are not enough; without adequate proof, credits will be denied.
• Practitioners should advise clients to maintain contemporaneous records and to gather supporting documentation well in advance of filing their returns.

Summary

Montes Gonzalez v. Commissioner is a reminder that in tax law even the most sympathetic facts cannot overcome a lack of substantiation. The IRS and the courts will not relax the statutory requirements, no matter how compelling the personal circumstances. For practitioners and taxpayers alike, the lesson is clear: documentation is essential when claiming child-related tax benefits. 

These issues will be explored in greater depth in our upcoming webinar, Identifying Qualifying Dependents and Qualifying Relatives, scheduled for Jan. 21, where we’ll break down the statutory tests, documentation standards and common traps that lead to disallowed credits. The rules are strict, the burden of proof is high, and the consequences of inadequate substantiation can be costly. In the world of tax credits, family alone is not enough; proof is paramount.