What it means
Many tax systems give a benefit, such as a credit or a deduction, to a taxpayer who supports a child or another family member. To stop the benefit being claimed by people who barely contribute, the rules include a test of how much support the taxpayer actually provides.
In the United States, this is known as the support test. Support covers the ordinary costs of living, including food, housing, clothing, education, medical care and transport.
The test compares the amount the taxpayer paid with the total cost of the person's support from all sources, such as the person's own earnings, public benefits and help from relatives. If the taxpayer's share is more than half, the test is passed.
There are different versions. For a qualifying child, the usual rule asks the opposite question, namely that the child must not have paid for more than half of their own support.
For another relative, the rule asks whether the taxpayer provided more than half of that person's support, and special arrangements apply to groups of relatives who share the cost. The test sits alongside others, such as relationship, residence, age and income tests, and all the relevant ones must be met.
The exact amounts and rules are set by the tax authority and change over time, so taxpayers and payroll teams should check the current guidance rather than rely on memory. Records of what was paid and by whom are essential if the claim is questioned.
The nuance is that the phrase "support test" is also used in a different sense in technical analysis, where traders say that a price "tests support" when it falls to a floor level. That is an unrelated idea, and this entry deals only with the tax rule.
Care with the context avoids confusion.
In practice
Real-world examples.
Example
A consultant pays for most of the living costs of her elderly mother, including $12,000 of rent and $3,000 of medical bills, while the mother's small pension covers the rest. The consultant adds up the figures and finds she provided more than half, so the test is passed.
Example
A father pays for his daughter's university fees and housing, totalling $20,000, while she earns $4,000 from a summer job and spends it on herself. Because she paid for well under half of her own support, the child version of the test is satisfied.
Example
Three adult siblings share the cost of caring for their uncle, each paying about a third. No single sibling provided more than half, so a special multiple-support arrangement is needed, and the siblings must agree who claims the benefit.
Formula
Calculation
Taxpayer's share of support = amount of support provided by the taxpayer / total support from all sources
Suppose a person's total living costs for the year were $24,000, covering housing, food, medical care and other needs. The taxpayer paid $15,000 of that and the person paid $9,000 from savings and part-time earnings. The taxpayer's share is 15,000 / 24,000 = 0.625, or 62.5%. Because 62.5% is more than half, the support test is met, and the taxpayer can go on to check the other tests for a dependant.Case study
Seen in the real world.
Redwood Payroll Services is an illustrative, fictional firm that helps small businesses with employee tax forms. A client's employee asked whether she could claim her adult brother as a dependant for the year.
The payroll adviser asked her to list all costs of her brother's support. His rent, food, transport and medical costs totalled $18,000, of which she had paid $7,500, he had paid $6,000 from earnings and a relative had paid $4,500.
The adviser calculated her share as 7,500 / 18,000, which is about 41.7%, below the 50% needed. In this illustrative case, the employee could not claim him, and the adviser explained that a multiple-support arrangement might have worked if the relatives had agreed in advance and kept records.
Watch out
Common mistakes.
- Counting only the cash the taxpayer handed over, and forgetting that the test compares it with all support from every source.
- Assuming that passing the support test is enough, when other tests such as relationship, residence and income must be met as well.
- Failing to keep records of payments, which makes it hard to prove the claim if the tax authority asks.
Questions
People also ask.
Does the support test look at the taxpayer's income?
No, it looks at how much of the dependant's living costs the taxpayer paid, not at how much the taxpayer earns.
What counts as support?
Food, housing, clothing, education, medical care, transport and similar living costs generally count, and the rules set out how to value items such as free lodging.
Where do I find the current rules?
The tax authority publishes the exact definitions, amounts and exceptions each year, and a tax adviser can confirm how they apply to your facts.
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