In real estate, a co-op is a form of housing where you buy shares in a corporation that owns an entire building, and those shares come with a lease giving you the exclusive right to live in a specific apartment. You don’t hold a deed to your unit. You hold stock, which is personal property, plus a proprietary lease. That single structural difference drives nearly everything else that makes co-op ownership distinct from owning a house or condominium.
How Ownership Works in a Co-op
A cooperative housing corporation holds title to the building and the land. When you buy in, you purchase a set number of shares in that corporation. The share count attached to each apartment usually reflects its size, floor, and desirability, so a larger unit on a higher floor carries more shares than a studio on a lower floor.
With the shares comes a proprietary lease (sometimes called an occupancy agreement). The lease is what actually gives you the right to occupy your unit for as long as you hold the stock. The corporation owns the walls, floors, and building systems. Your interest is classified as personal property, not real property.
Federal tax law defines a cooperative housing corporation as one that has a single class of stock, entitles each stockholder to occupy a dwelling unit, and derives at least 80 percent of its gross income from its resident shareholders.1Office of the Law Revision Counsel. 26 U.S. Code 216 – Deduction of Taxes, Interest, and Business Depreciation by Cooperative Housing Corporation Tenant-Stockholder A co-op can be organized as a nonprofit or as a standard corporation, but it has to meet these criteria for shareholders to claim the tax deductions discussed below.
Co-op vs. Condo
The clearest way to understand what a co-op is in real estate is to compare it to the thing people most often confuse it with. A condominium owner receives a deed to the individual unit and holds it as real property. A co-op owner receives shares and a lease. From that distinction, several practical differences follow.
- Financing. Condo buyers get traditional mortgages secured by the unit. Co-op buyers get share loans secured by stock and the proprietary lease. Because the collateral is personal property, the lender perfects its interest by filing a UCC-1 financing statement rather than recording a mortgage against real estate.2Fannie Mae. Co-op Share Loan Documentation Requirements
- Down payments. Some condo programs allow 3 to 5 percent down. Co-op boards frequently require 20 to 50 percent, because the board sets its own thresholds on top of what any lender requires.
- Approval of the buyer. Condo purchases rarely need board approval of the buyer. Co-op boards review detailed financial packages, interview applicants, and can reject them without stating a reason, so long as the decision doesn’t violate fair housing law.
- Resale. A condo seller can accept any qualified buyer. A co-op seller needs a buyer the board will approve, which narrows the pool and can slow things down.
- Monthly fees. Both charge monthly fees, but co-op maintenance usually rolls property taxes and the building’s underlying mortgage interest into one number, so the headline figure often looks higher even though significant portions are deductible.
What It Takes to Buy In
Buying co-op shares involves a more demanding financial review than a typical home purchase. You submit an application package to the board that generally includes several years of tax returns, recent bank statements, and documentation of your assets and debts. The board uses it to judge whether you can comfortably carry the monthly cost over the long term.
Co-op boards often set stricter benchmarks than a bank would. Many cap a buyer’s debt-to-income ratio at 25 to 28 percent, well below the 36 to 50 percent range conventional mortgage lenders use.3Fannie Mae. B3-6-02, Debt-to-Income Ratios Boards also commonly expect you to show 12 to 24 months of housing costs in liquid assets after closing. The logic is simple: if you lose your income, the board wants to know you can keep paying maintenance.
Down payment expectations vary by building. Twenty percent is a floor; in competitive urban markets, 30 to 50 percent is common. Fewer lenders offer share loans than offer condo mortgages, and the ones that do may charge slightly higher rates or require more documentation.
The Board Approval Process
After you submit your package, the elected board of directors reviews your financial disclosures and references. Review typically runs several weeks. If you clear the initial screening, the board invites you to an interview, usually 30 to 60 minutes, in person or by video.
Board members may ask about your work, your plans for the unit, and your willingness to follow building rules. The point is less interrogation than confirming you’ll be a reasonable neighbor. The board votes afterward and usually responds within a week or two.
A co-op board can reject an applicant without giving a reason. That discretion has one firm limit: the federal Fair Housing Act prohibits housing decisions based on race, color, religion, sex, national origin, familial status, or disability.4Office of the Law Revision Counsel. 42 U.S. Code 3604 – Discrimination in the Sale or Rental of Housing and Other Prohibited Practices Many state and local laws add protected categories on top. A rejection that appears to rest on any protected characteristic can expose the board to a discrimination claim.
Monthly Maintenance and Special Assessments
Once you move in, you pay a monthly maintenance fee covering the building’s collective operating costs. Unlike a condo’s common charges, co-op maintenance usually bundles several categories of expense into a single payment:
- Your share of the real estate taxes the corporation pays on the entire building.
- Your share of the interest on the corporation’s underlying mortgage, if the building carries one, as most do.
- Operating costs such as staff salaries, insurance, heating fuel, water, elevator maintenance, and common-area utilities.
Your portion of the total budget is calculated from the number of shares assigned to your unit relative to total shares outstanding.5Internal Revenue Service. Publication 530 (2025), Tax Information for Homeowners – Section: Special Rules for Cooperatives
Beyond regular maintenance, the board can levy special assessments. These are one-time charges for major capital projects like a new roof, a boiler replacement, or facade repairs. They can run into tens of thousands of dollars per unit. Once the board votes, shareholders are obligated to pay. Falling behind on an assessment carries the same consequences as falling behind on maintenance: legal action and potential loss of your shares.
Tax Treatment
Even though you don’t hold a deed, federal tax law treats co-op shareholders much like homeowners for deduction purposes. You can deduct your proportionate share of two costs the corporation pays: the building’s real estate taxes and the interest on the corporation’s mortgage.6eCFR. 26 CFR 1.216-1 – Amounts Representing Taxes and Interest Paid to Cooperative Housing Corporation The share is based on the ratio of your shares to total shares outstanding.
The co-op reports your deductible share of mortgage interest on Form 1098 each year, the way any mortgage lender would.7Internal Revenue Service. Instructions for Form 1098 Your share of property taxes is deductible on your federal return, subject to the $10,000 state and local tax cap. Interest on your personal share loan is deductible as mortgage interest, so you can potentially deduct both your own loan interest and your share of the building’s mortgage interest.
When you sell your shares, you may qualify for the capital gains exclusion that applies to the sale of a primary residence. If you have owned and lived in the unit for at least two of the five years before the sale, you can exclude up to $250,000 in gain, or $500,000 for married couples filing jointly.8Office of the Law Revision Counsel. 26 USC 121 – Exclusion of Gain From Sale of Principal Residence The statute specifically extends this benefit to tenant-stockholders in cooperative housing corporations.
One limit worth knowing: amounts you pay to the corporation that go to capital expenditures, such as a new boiler or paying down the building’s mortgage principal, are not deductible. Instead, they increase your cost basis in the shares, which reduces your taxable gain when you sell.6eCFR. 26 CFR 1.216-1 – Amounts Representing Taxes and Interest Paid to Cooperative Housing Corporation
Selling Co-op Shares
Selling a co-op is more involved than selling a house or condo. Your buyer must pass the same board approval you did, so a deal can collapse if the board rejects the purchaser. Many co-op governing documents also give the corporation a right of first refusal, meaning the corporation can buy your shares at the offered price before you sell to an outside buyer. If the corporation doesn’t exercise the right within a set window (often 30 to 60 days), the sale can proceed.
Many co-ops also charge a transfer fee commonly called a flip tax. It may be a percentage of the sale price, a percentage of the seller’s profit, or a flat amount per share. Rates vary, but 1 to 3 percent of the sale price is common, and the seller usually pays it. The money goes to the corporation’s reserve fund or operating budget.
Between board approval, the right of first refusal, and the flip tax, co-op sales generally take longer and carry more uncertainty than other types of housing transactions. Buyers who need to close quickly or who have unconventional finances may not survive the board process.
Risks Specific to Co-op Ownership
The shared financial structure creates risks that don’t exist in traditional homeownership. The biggest is the underlying mortgage. The corporation, not individual shareholders, holds the building’s loan, which means shareholders are collectively exposed to it. If enough shareholders stop paying maintenance and the corporation can’t cover its mortgage, the building could face foreclosure, and even shareholders current on everything they owe could lose their investment.
A related risk is neighbor defaults. When a shareholder stops paying, the remaining shareholders effectively absorb the shortfall through higher fees or reduced services until the board resolves it. The board can pursue the defaulting shareholder, including eviction through landlord-tenant proceedings and forced sale of the shares, but that process takes time.
Before buying, read the corporation’s financial statements. The size of the reserve fund, the percentage of units in arrears, and the remaining term on the underlying mortgage are the figures that most directly tell you how much financial pressure the building is under.
Rules You Live Under
Living in a co-op means following rules set by the corporation’s bylaws and house rules. These documents tend to be more detailed than what you’d find in a condo association.
- Most co-ops limit how often and how long you can sublet, commonly allowing it for only one or two years within a longer window such as every five years. Some prohibit subletting entirely. Where it’s allowed, the board typically has to approve the subtenant, and a maintenance surcharge is common.
- Interior renovations require written approval through an alteration agreement, including architectural plans and proof of insurance. The corporation owns the physical structure and has a direct interest in work that could affect building systems.
- Pet policies often include breed restrictions and weight limits.
- House rules commonly set quiet hours and regulate activities that affect neighbors.
The tradeoff built into the cooperative model: you get a voice in how the building is run through board elections and shareholder votes, and you accept more constraints on individual autonomy than a homeowner or condo owner would.
Limited Equity Co-ops
One variation worth flagging: not all co-ops operate on the open market. Limited equity cooperatives cap how much a shareholder can sell their shares for, using a formula written into the bylaws. Resale prices are tied to inflation or a small fixed appreciation rate rather than market conditions. Share prices in these buildings are often very low, sometimes just a few hundred dollars, because the building’s costs are covered mainly through the mortgage and subsidies rather than through large share purchases. You get in cheaply and give up the ability to capture full market appreciation. These co-ops typically exist in communities that received government subsidies or nonprofit development funding, and they function as long-term affordable housing rather than wealth-building vehicles.