An owner-occupied duplex, where you live in one unit and rent out the other, sits at a useful intersection of homeownership and real estate investing. Lenders treat it as a primary residence, which means residential loan terms and small down payments. The IRS treats half of it as a rental, which means depreciation and expense deductions but also a more complicated tax return. And once a tenant moves in next door, federal disclosure rules, fair housing law, and landlord insurance requirements all apply, even though you’re just living at home.
Here is what changes when you buy a two-unit property as your primary residence.
Financing a Two-Unit Home You’ll Live In
Because you plan to occupy one of the units, lenders classify the purchase as a primary residence rather than an investment property. That single classification opens the door to government-backed and conventional residential loans, better interest rates, and the ability to count expected rent toward your qualifying income.
Down Payments
Conventional loans backed by Fannie Mae and Freddie Mac allow as little as 5% down on a two-unit property when you occupy one unit. That threshold took effect in November 2023; before then, a two-unit conventional purchase required 15% down.1Fannie Mae. Responsibly Increasing Affordable Housing Supply and Access to Credit FHA loans go lower, requiring 3.5% down regardless of unit count, provided the property is your primary residence.2U.S. Department of Housing and Urban Development. How Can FHA Help Me Buy a Home Eligible veterans and service members can use a VA loan to buy a property of up to four units with zero down and no private mortgage insurance.3U.S. Department of Veterans Affairs. VA Home Loan Guaranty Buyers Guide
Counting Rent Toward Qualification
Lenders will let you use projected rent from the vacant unit to increase your qualifying income. Fannie Mae’s rule: take the gross monthly rent from a lease or the appraisal’s market rent estimate, multiply by 75%, and add that figure to your income when calculating debt-to-income ratio.4Fannie Mae. Rental Income The 25% haircut accounts for vacancies and maintenance. Freddie Mac applies the same 75% factor.5Freddie Mac. Freddie Mac Single-Family Seller Servicer Guide – Rental Income That extra income can meaningfully increase the loan amount you qualify for.
2026 Loan Limits
Two-unit loan limits are set well above single-family limits. For 2026, the conforming loan limit on a two-unit property is $1,066,250 in most of the country and up to $1,599,375 in designated high-cost areas.6Fannie Mae. Loan Limits FHA limits for two-unit properties range from $693,050 up to $1,599,375 depending on county.7U.S. Department of Housing and Urban Development. HUD Federal Housing Administration Announces 2026 Loan Limits In high-cost metros, those limits give significant buying power on a residential loan with a small down payment.
The Occupancy Requirement
All of the favorable terms above depend on you actually living in the property. FHA requires you to move in within 60 days of closing and use the unit as your primary residence for at least the first year. Conventional lenders impose similar occupancy conditions. Misrepresenting your intent to occupy can be mortgage fraud and, at minimum, force a refinance to investment-property terms.
Splitting the Building for Taxes
Once you’re a landlord, you’re running two properties on paper: your home and a rental. Rental income and expenses go on Schedule E; your personal-use portion of mortgage interest and property taxes can be itemized on Schedule A the way any homeowner would deduct them.8Internal Revenue Service. Instructions for Schedule E Supplemental Income and Loss Many costs apply to the whole building, so you need a defensible method for dividing them.
Allocating Shared Expenses
The IRS accepts any reasonable method to split shared costs like mortgage interest, insurance, and common-area utilities. The two common approaches are dividing by number of rooms or by square footage.9Internal Revenue Service. Publication 527 – Residential Rental Property If the rental unit is 900 square feet and the whole building is 1,800, you deduct 50% of each shared expense on Schedule E. Costs that apply only to the rental unit, like repainting a tenant’s bedroom, are 100% deductible on Schedule E.
Pick one method and stick with it. Switching year to year invites scrutiny. A dedicated bank account for the rental keeps income and expenses from mixing with personal money and makes the arithmetic straightforward at tax time.
Depreciation
Depreciation is the largest tax benefit on the rental side. The IRS lets you deduct the cost of the building structure (not the land) over 27.5 years under the Modified Accelerated Cost Recovery System.10Office of the Law Revision Counsel. 26 U.S. Code 168 – Accelerated Cost Recovery System Only the rental share qualifies. If you allocate 50% of the property to the rental and the building (excluding land) cost $300,000, you depreciate $150,000 over 27.5 years, roughly $5,455 a year in non-cash deductions.
This deduction often produces a paper loss on the rental even while rent is coming in each month, and that loss can offset other income. You must claim depreciation every year. If you skip it, the IRS still treats the deduction as taken when you eventually sell, so you lose the annual benefit without avoiding the tax bill at the back end.
The 20% Qualified Business Income Deduction
Rental income may qualify for the Section 199A deduction, worth up to 20% of qualified business income from a pass-through activity. The IRS provides a safe harbor: perform at least 250 hours of rental services per year and keep contemporaneous records (logs of what you did, when, and for how long), and the rental qualifies as a business for the deduction.11Internal Revenue Service. IRS Finalizes Safe Harbor to Allow Rental Real Estate to Qualify as a Business for Qualified Business Income Deduction Those 250 hours include collecting rent, coordinating repairs, screening applicants, and keeping records. The deduction phases out at higher incomes.
When You Sell
Selling triggers two tax calculations because the personal and rental portions are treated as distinct assets. The personal half may qualify for the Section 121 home sale exclusion: up to $250,000 of gain excluded for a single filer, $500,000 for married filing jointly, provided you owned and lived in the unit for at least two of the five years before the sale.12Internal Revenue Service. Topic No 701 Sale of Your Home
The rental portion does not get that exclusion. IRS Publication 523 is explicit: with a duplex where one unit was rented out, you allocate gain between residential and rental portions, and the rental portion’s gain is taxable.13Internal Revenue Service. Publication 523 – Selling Your Home Use the same allocation method you used for depreciation.
On top of capital gains, the rental portion faces depreciation recapture. Every dollar of depreciation claimed (or that you were entitled to claim) is taxed at up to 25% when you sell.14Office of the Law Revision Counsel. 26 U.S. Code 1(h) – Tax Imposed If you claimed $50,000 of depreciation over your ownership period, you owe recapture on the full $50,000. Any remaining profit on the rental portion is then taxed at your long-term capital gains rate.
Federal Lead Paint Disclosure
If the building was constructed before 1978, federal law requires you to give every new tenant specific lead-based paint disclosures before they sign a lease. Provide a copy of the EPA pamphlet “Protect Your Family From Lead in Your Home,” disclose any known lead-based paint or hazards, and include a lead warning statement in the lease.15U.S. Environmental Protection Agency. Real Estate Disclosures About Potential Lead Hazards The requirement applies to most pre-1978 housing, including owner-occupied duplexes where one unit is rented.16U.S. Environmental Protection Agency. What Is Target Housing
Narrow exemptions cover short-term leases of 100 days or fewer, housing certified lead-free by a licensed inspector, and housing designated for the elderly or persons with disabilities (unless a child under six lives or is expected to live there). Violations carry federal penalties, and a tenant harmed by lead exposure can pursue civil liability.
Fair Housing When You Live Next Door
The Federal Fair Housing Act prohibits housing discrimination based on race, color, religion, sex, national origin, familial status, and disability, and it reaches advertising, showing the unit, screening, lease terms, and every part of the landlord-tenant relationship.17U.S. Department of Justice. The Fair Housing Act
The Owner-Occupied Exemption Is Narrower Than It Sounds
Federal law includes an exemption for owner-occupied buildings with no more than four units. Under 42 U.S.C. 3603(b)(2), the owner of a duplex who lives in one unit is technically exempt from some of the Act’s prohibitions on tenant selection.18Office of the Law Revision Counsel. 42 U.S. Code 3603 – Effective Dates of Certain Prohibitions Two big holes limit the exemption. It does not cover advertising, so discriminatory language in a listing is prohibited regardless of your occupancy. And many state and local fair housing laws are stricter and do not recognize the exemption at all. The safe approach: treat every applicant identically and keep protected characteristics out of your screening and advertising.
Screening
Screening matters more here than in almost any other rental setup because you’ll be sharing walls with whoever moves in. A consistent, documented process protects you legally and practically: pull a credit report, verify income (a common threshold is gross monthly income of at least two and a half to three times rent), confirm employment, and call previous landlords. Apply the same criteria to every applicant. Rejecting one applicant on gut feeling while approving a similarly situated applicant of a different background is a textbook fair housing complaint.
Assistance Animals
A “no pets” lease does not override the Fair Housing Act’s reasonable accommodation requirement for assistance animals. Both trained service animals and emotional support animals are covered. A tenant with a disability-related need can request the accommodation, and you must grant it unless it would impose an undue financial burden, fundamentally change your operations, or the specific animal poses a direct threat.19U.S. Department of Housing and Urban Development. Assistance Animals You cannot charge a pet deposit or pet fee for an approved assistance animal. Living in the same building does not exempt you from this rule, and it’s one of the most common complaints against small landlords.
Lease and Habitability Basics
Use a written lease even when the tenant is someone you know. Cover rent amount and due date, which party pays each utility, maintenance responsibilities, rules for shared spaces (yard, driveway, laundry), quiet hours, and how the tenancy ends. Informal arrangements tend to hold up until the first real dispute.
You have a legal obligation to keep the rental unit habitable. In most states, the implied warranty of habitability requires functioning plumbing, heating, electricity, and structural integrity, and repairs within a reasonable time. If conditions deteriorate, tenants in many states can withhold rent, repair-and-deduct, or break the lease without penalty. Living next door makes it harder to argue you didn’t know about a problem.
Proximity creates management issues that off-site landlords don’t face. Tenants will knock at odd hours for minor things. A maintenance request form or a text-based system keeps requests documented and the relationship professional. Handle noise complaints and rule violations through the lease, not through hallway conversations.
Security Deposits
Security deposit rules vary by state, but two are near-universal: return the deposit within a set number of days after move-out, and provide an itemized list of any deductions. Many states also require the deposit to sit in a dedicated account, separate from personal funds. Commingling can trigger penalties, forfeiture of the deposit, and in some states liability for the tenant’s attorney fees.
A separate operating account for the rental also makes Schedule E simpler. If you’re pursuing the QBI safe harbor, you need contemporaneous records of your rental activity anyway. Clean records from day one beat reconstructing them under audit.
Insurance That Actually Covers a Rented Unit
A standard homeowner’s policy (HO-3) covers the unit you live in but typically excludes or denies claims involving tenant-occupied space. You need a hybrid: homeowner’s coverage for your unit and a rental dwelling policy (often called DP-3 or a landlord policy) for the tenant’s unit. The landlord policy covers the structure and your liability as the rental owner. It does not cover the tenant’s belongings; your tenant should carry renter’s insurance for that. Tell your insurer that one unit is rented. Failing to disclose the rental use can void the policy if you file a claim.
Two add-ons earn their cost. Loss-of-rent coverage replaces income you lose if a covered event, such as fire or storm damage, makes the tenant’s unit uninhabitable. Most policies cap the benefit at 12 months or until repairs are finished, whichever comes first. A personal umbrella policy adds liability protection above the limits of both your homeowner’s and landlord policies. If a tenant or guest is seriously injured on the property and the judgment exceeds your underlying coverage, the umbrella picks up the difference. As an on-site landlord with foot traffic next door, that additional liability layer is worth the premium.