A multiple support agreement is the arrangement that lets one member of a group of contributors claim a dependent when no single person paid over half of that person’s support. It works by deeming the support test met rather than by waiving it.
For purposes of paragraph (1)(C), the qualifying relative condition requiring the taxpayer to provide over one-half of the individual’s support for the calendar year, over one-half of the support of an individual for a calendar year shall be treated as received from the taxpayer if four conditions are met (26 U.S.C. 152(d)(3)). Those opening words are the boundary of the whole rule, and the rest of the dependency conditions are untouched by it, set out in dependents.
The Four Conditions, All Required
No one person contributed over one-half of such support.
Over one-half of such support was received from 2 or more persons each of whom, but for the fact that any such person alone did not contribute over one-half of such support, would have been entitled to claim such individual as a dependent for a taxable year beginning in such calendar year.
The taxpayer contributed over 10 percent of such support.
And each person described in the second condition, other than the taxpayer, who contributed over 10 percent of such support files a written declaration, in such manner and form as the Secretary may by regulations prescribe, that such person will not claim such individual as a dependent for any taxable year beginning in such calendar year (26 U.S.C. 152(d)(3)).
The second condition is the one that gets read too quickly. It does not ask who paid; it asks who would have been entitled to claim the person as a dependent but for the support shortfall. Somebody who fails a different dependency test is not in the group at all, however much they paid.
Who Counts as an Eligible Person
The form puts the same test in one sentence. An eligible person is someone who could have claimed a person as a dependent except that he or she did not pay over half of that person’s support (IRS, Form 2120, Rev. December 2025).
The regulation’s own worked example shows what that excludes. Where an individual’s support came from social security, an unrelated neighbour, a brother, a daughter and a son, the brother, the daughter and the son are each persons who but for the fact that none contributed more than half could claim him as a dependent, so those three are the group. The neighbour contributed over 10 percent of the support, but since he is an unrelated neighbour he does not qualify as a member of the group for the purpose of the multiple support agreement, and the daughter, who did not contribute more than 10 percent, is neither entitled to claim the dependent nor required to furnish a written declaration (26 CFR 1.152-3(b), Example 2).
A second example fixes how many declarations are needed. Where four brothers contributed the entire support of their mother in percentages of 30, 20, 29 and 21, any one of them could claim her if he obtained a written declaration from each of the other brothers, and even though two of them together contributed more than one-half of her support, the one claiming her would be required to obtain written declarations from all three of the others, since each of those three contributed more than 10 percent and, but for the failure to contribute more than half, would have been entitled to claim her (26 CFR 1.152-3(b), Example 1).
Reaching half between two of the contributors does not shorten the paperwork. Every other over-10-percent member of the group has to sign.
It Does Not Reach a Qualifying Child
The rules for multiple support agreements apply to claiming an exemption for a qualifying relative and do not apply to claiming an exemption for a qualifying child (IRS, Form 2120, Rev. December 2025). The statute says the same thing structurally, by placing the rule inside the qualifying relative definition and pointing it at that definition’s support paragraph (26 U.S.C. 152(d)(3)). What has to be true for someone to be a qualifying relative in the first place is in qualifying relative.
What Is Filed and What Is Kept
The two halves are easy to swap, and swapping them is the common filing error.
Filed with the return, for a taxable year beginning after December 31, 2001: a statement identifying each of the other persons who contributed more than 10 percent of the support of the individual and who, but for the failure to contribute more than half, would have been entitled to claim the individual as a dependent, and a statement indicating that the taxpayer obtained a written declaration from each of those persons waiving the right to claim the individual (26 CFR 1.152-3(c)(2)). Form 2120, Multiple Support Declaration, can be used for this purpose (IRS, Publication 501).
Kept, not filed: the waiver declarations themselves. For a taxable year beginning after December 31, 2001 the taxpayer must retain the waiver declarations and should be prepared to furnish them and any other information necessary to substantiate the claim, which may include a statement showing the names of all contributors, whether or not members of the group, and the amount contributed by each (26 CFR 1.152-3(c)(3)). The form says it in plainer words: do not file the signed statement with your return, keep it for your records and be prepared to furnish it and any other information necessary to show that you qualify (IRS, Form 2120, Rev. December 2025).
Each signed statement has required contents. It must include the calendar year the waiver applies to, the name of the qualifying relative the eligible person helped to support, and the eligible person’s name, address and social security number (IRS, Form 2120, Rev. December 2025).
The form has room for four. If there are more than four other eligible persons, a statement with the required information is attached to the return (IRS, Form 2120, Rev. December 2025).
A Citation Trap in the Regulation
The regulation and the statute do not use the same address for this rule, and a citation copied from one into the other will not resolve.
Throughout, 26 CFR 1.152-3 states the rule as section 152(c), including in its opening line, its examples and its filing paragraphs (26 CFR 1.152-3). The current statute carries the multiple support rule at section 152(d)(3), under the heading Special rule relating to multiple support agreements (26 U.S.C. 152(d)(3)). Section 152(c) in the current statute is the qualifying child definition, which is a different rule entirely and the one the form says multiple support agreements do not reach.
So a workpaper that cites the regulation’s section 152(c) references is citing a subsection number that no longer holds the rule. Cite the regulation by its own section number (26 CFR 1.152-3) and the statute by its current one (26 U.S.C. 152(d)(3)).
Two Rules It Switches Off
Head of household is the first. If you can claim a person as a dependent only because of a multiple support agreement, that person is not a qualifying person for head of household (IRS, Publication 501). A taxpayer who wins the dependent this way does not win the filing status with it, and the statuses that turn on a qualifying person are set out in filing status.
The special rule for divorced or separated parents is the second. If the support of the child is determined under a multiple support agreement, the special support test for children of divorced or separated parents, or parents who live apart, does not apply (IRS, Publication 501).
Common Questions
No. Where two or more persons who could each claim the person but for the support test together provide more than half of the support, you can agree that any one of you who individually provides more than 10 percent of the support, but only one, can claim that person as a dependent, and each of the others must sign a statement agreeing not to claim the person for that year (IRS, Publication 501).
Only the members of the group who contributed over 10 percent, and not the taxpayer doing the claiming (26 U.S.C. 152(d)(3)(D)). Someone who contributed less than that signs nothing and is not required to furnish a declaration at all (26 CFR 1.152-3(b), Example 2).
Not necessarily. You can claim someone as a dependent under a multiple support agreement for someone related to you or for someone who lived with you all year as a member of your household (IRS, Publication 501). What matters is that each member of the group would have been entitled to claim the individual but for the support shortfall, which is a test about the claimant’s own relationship to the person, not about the group’s relationship to each other.
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