A “self-rental” is what the IRS calls it when you rent property to a business in which you materially participate. Doctor owns the building her practice operates out of. S-corp owner owns the warehouse his business uses. Married couple where one spouse owns the LLC that owns the building, the other owns the operating company. All self-rentals.
Why the income gets recharacterized
The general rule is that rental income is passive. Congress and Treasury did not want taxpayers to use that against the system by renting to themselves and creating fake passive income to soak up unrelated passive losses. So the regulation flips the script: if you materially participate in the business renting from you, the net rental income is non-passive (active).
But the recharacterization only runs in one direction. The same rule does not recharacterize losses. A loss on the self-rental stays passive, which means it can only offset other passive income, not the business income next door.
The grouping fix
The most common fix is the grouping election. If you group the self-rental with the operating business as a single activity (which you usually can when ownership matches across both), the whole combined unit is non-passive. Losses on the building flow against the business’s income on the same return. We covered the mechanics in the grouping elections article.
The election is a written statement filed with your return. Miss the statement, miss the benefit.
The NIIT bonus
If your self-rental income is recharacterized as non-passive (with or without a grouping), it is also excluded from the 3.8% Net Investment Income Tax for high earners. That can be worth another 3.8% on the rent each year, on top of the loss-utilization benefit.
What "fair market rent" means and why the IRS cares
The rent has to be set at arm’s length. That means roughly what an unrelated landlord would charge for the same building. If the rent is too high, the IRS can adjust it under § 482. If it is too low, the same § 482 authority cuts the other way. Either adjustment can trigger valuation-misstatement penalties (20% of the underpayment for substantial; 40% for gross). Comparable-property data, a written lease, and a periodic refresh of market rates are the file you want.
What happens when you sell the business but keep the building
The self-rental classification does not immediately switch off the day you sell the operating business. There is a five-year look-back rule for material participation: if you materially participated in the business for five of the prior ten years, you are still treated as a material participant for some time after the sale. That means the self-rental recharacterization keeps running for a while. Plan the sale knowing this is coming and where the rent income will land.
Partial buildings and mixed tenants
Two units in a building, one rented to your business and one to a stranger? You can group just the self-rental portion with the business. The third-party portion stays a separate, ordinary passive rental. The grouping does not extend to space the business does not occupy.