Shared Household Expenses When Only One Person Owes the IRS

"My wife doesn't owe anything. Why does the IRS want her income?" It is a fair question, and it comes up whenever only one spouse is liable. The answer is that the IRS is not trying to collect from her. It is trying to figure out how much of the household's rent, groceries and utilities you actually pay. Her income is how it gets there.

The basic idea

IRM 5.15.1.5 says a taxpayer "is only allowed those expenses that meet the necessary expense test... that they are required to pay." When a liable taxpayer lives with a non-liable person who shares expenses, "it is necessary to review other income coming into the household and expenses that are shared with the non-liable person to determine the taxpayer's allowable portion of the shared household expenses."

And the reassurance: "Although the assets and income of a non-liable person may be reviewed to determine the taxpayer's portion of the shared household income and expenses, they are generally not included when calculating the amount the taxpayer can pay."

The exception: community property states

The big exception is community property law. IRM 5.15.1.5 tells employees to follow community property laws "to determine what assets and income of the non-liable spouse are subject to collection of the tax." It lists the community property states as Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington and Wisconsin, notes that Puerto Rico is a community property jurisdiction, and describes Alaska as opt-in. Florida is not on the list.

A non-liable spouse who disagrees with including their income or assets under community property rules can seek help from the Taxpayer Advocate Service.

The percentage method, step by step

IRM 5.15.1.5 lays out the steps:

1. Determine total actual household income and expenses.
2. Determine what percentage of total household income the taxpayer contributes. Divide the taxpayer's income by the total household income.
3. Determine allowable expenses.
4. Separate shared expenses from expenses that are the taxpayer's sole responsibility, such as the taxpayer's own child support, allowable student loans, or union dues.
5. Apply the taxpayer's percentage to the shared expenses, and verify the taxpayer actually contributes that amount.

Expenses that are solely the taxpayer's responsibility are allowed in full. The taxpayer gets nothing for the non-liable person's discretionary spending.

The IRM's simple example: the taxpayer earns $20,000 and the non-liable person earns $5,000, so household income is $25,000. The taxpayer's share is 80 percent. Shared allowable expenses are multiplied by 80 percent.

How each standard is split

This is where it gets technical, and where it helps to know the rules cold. IRM 5.15.1.5 treats each standard differently:

Notice the asymmetry. For National Standards, the taxpayer is never pushed below the one-person standard. For housing and transportation, the taxpayer is never allowed more than the one-person standard, and may be allowed less.

Running it with 2026 numbers

Take a married couple in Hillsborough County, no children. The liable spouse earns $2,000 a month and the non-liable spouse earns $6,000. The liable spouse's share is 25 percent. They pay $2,600 for rent and utilities.

• National Standard. The June 29, 2026 standard for two persons is $1,558. Twenty-five percent is $389.50. The one-person standard is $867. The greater is $867.
• Housing. The two-person Hillsborough standard is $2,435; 25 percent is $608.75. Twenty-five percent of the $2,600 actual is $650. The one-person standard is $2,073. The lesser is $608.75.
• Health care. Two people under 65 is $180; 25 percent is $45. One person is $90. The greater is $90.

Then add the liable spouse's sole-responsibility expenses, such as taxes withheld from their own pay, and the transportation allowance. You can see how quickly the result depends on the income split.

Roommates and renting a room

When income is not commingled and household expenses are split fairly among cohabitants, IRM 5.15.1.5 says the total allowable expense "should not exceed the total allowable housing standard for the taxpayer," and it "would not be necessary to obtain the income or expense information of the non-liable person(s)." The IRM's example: a taxpayer sharing with a roommate receives the full National Standard and health care standard for one person, and the amount actually paid up to the one-person housing and transportation standards.

If you rent a room from a non-liable property owner, a rental agreement or signed statement from the owner should support not requiring the owner to share personal financial information.

When the non-liable person will not cooperate

Some partners refuse to share their finances, and the IRS cannot force them to in this context. IRM 5.15.1.5 covers it: if the non-liable person's income is not provided and cannot be verified internally, the employee will "allow the liable taxpayer only the national and local standards for one person plus any allowable and verifiable dependents." Where the non-liable person refuses to provide supporting documentation, the employee "may consider allowing up to 50 percent of the necessary shared household expenses if those expenses are reasonable."

And the privacy protection runs both ways. If the IRS checks the non-liable person's information internally, "this information cannot be provided to the taxpayer." Sharing it with anyone other than that person, without consent, would be a disclosure violation under IRC 6103.

Adult children at home

IRM 5.15.1.12 says income earned by a dependent child, reported on the child's own return, generally is not household income. But if "an independent adult child is living with the taxpayer and contributing to the household income used to pay living expenses," that income may be included in a shared expense analysis.

The IRM's own detailed example

IRM 5.15.1.5 includes a full worked example with a family of four where the liable spouse earns $3,000 of $15,000 in monthly household income, a 20 percent share. A few results from that table show how the rules play out:

• The National Standard is allowed at the one-person amount because it is greater than 20 percent of the four-person amount.
• Housing is allowed at 20 percent of the four-person standard because that is the lowest of the three possible figures.
• A $600 tax payment that is the liable spouse's own responsibility is allowed in full.
• Child support paid by the non-liable spouse for a child from a prior marriage is allowed at zero, because it is the non-liable spouse's obligation.
• A $100 court-ordered payment owed by the liable spouse is allowed in full.

The dollar figures in that example are illustrative and predate the current standards, but the method is the method. Each expense is sorted into shared or sole responsibility, then measured.

Practical tips

• Separate your own obligations from household ones before you fill out the form, and attach proof of the ones that are yours alone.
• Talk to the non-liable person before the IRS does. They need to know why their income is being asked about and that it is generally not being collected from.
• If your contributions to the household do not match your income share, document what you actually pay. The IRM tells employees to verify that the taxpayer actually contributes the calculated amount.

Shared household analysis is math, not judgment. Know the rules, run the numbers before the IRS does, and you will know whether a hardship request makes sense in your household.