A housing co-op works by turning the building into a corporation and its residents into shareholders. When you buy into a co-op, you’re not buying real estate. You’re buying shares of stock in the corporation that owns the building, and those shares come with a proprietary lease giving you the exclusive right to live in a specific unit. That makes you both an owner of the company and a tenant under its lease at the same time, and that dual status shapes how you finance the purchase, what you pay each month, who has to approve you moving in, and what happens when you leave.
What You Actually Own
A conventional home purchase ends with a deed transferring a piece of real estate to the buyer. A co-op purchase ends with a stock certificate and a lease. The corporation holds title to the entire building and the land under it. Each apartment is assigned a number of shares based on factors like square footage, floor level, and layout, so a larger unit on a higher floor carries more shares. Those shares determine your vote at shareholder meetings and your slice of the building’s expenses.
The proprietary lease (sometimes called an occupancy agreement) spells out your right to occupy your unit, your obligation to pay monthly charges, and the rules you agree to follow. It isn’t a one-year rental lease. It runs for decades and renews automatically as long as you stay current on your obligations.
Because co-op shares are legally classified as personal property rather than real property, almost everything downstream behaves a little differently from a house or condo. Lenders don’t record a mortgage. Estates don’t transfer a deed. And the corporation, not you, is the entity that owns the physical apartment.
Co-op vs. Condo
The confusion between co-ops and condos is understandable since both involve multi-unit buildings with shared walls. The legal structure is what separates them. A condo buyer receives a deed to an individual unit and jointly owns the common areas with the other unit holders. A co-op buyer receives shares of corporate stock and a lease.
That single distinction changes almost everything else. Financing is more flexible for condos because lenders treat them like any other real estate. Co-op boards often require buyers to put down 20% to 50% of the purchase price, compared to as little as 3% to 5% for some condo purchases. Condo associations generally can’t block a sale as long as the buyer meets basic financial qualifications. Co-op boards have broad authority to approve or reject purchasers, including the power to conduct personal interviews and demand extensive financial documentation.
Getting Approved by the Board
Buying into a co-op isn’t just a deal between buyer and seller. The board must approve every purchase, and this is where most of the friction lives. You submit a board package with extensive financial documentation: typically two years of federal income tax returns, bank and investment statements, a personal financial statement listing assets and liabilities, and verification of employment including salary and job tenure. Most buildings also require personal and professional reference letters. The managing agent provides the official application and usually charges a non-refundable processing fee.
If the paperwork passes, the board invites you to an in-person interview, usually in a common area of the building and typically 30 to 60 minutes long. Board members use it to clarify financial details and get a sense of whether you’ll fit in. The atmosphere can feel high-stakes because the board’s decision is essentially final.
Boards in most jurisdictions are not required to give a reason when they reject an applicant. There’s a limit, though. The federal Fair Housing Act prohibits refusing to sell housing to anyone because of race, color, religion, sex, familial status, or national origin, and co-ops are not exempt.1Office of the Law Revision Counsel. 42 USC 3604 Discrimination in the Sale or Rental of Housing and Other Prohibited Practices Many state and local laws add categories such as sexual orientation, age, disability, marital status, and lawful source of income. A board can reject someone it genuinely believes poses a financial risk. It cannot reject someone because of a protected characteristic.
Financing a Co-op Purchase
Since you’re buying shares rather than real estate, the loan you take out is called a share loan. It functions much like a mortgage: you borrow money, pay it back monthly with interest, and lose the collateral if you default. The legal mechanics differ. Instead of recording a mortgage against real property, the lender files a UCC-1 financing statement to perfect its security interest in your shares and proprietary lease.
Most co-op boards also require the lender to sign a recognition agreement before approving a financed purchase. This three-way contract between you, your lender, and the co-op corporation sets the ground rules if you stop paying. The co-op agrees to notify the lender if you fall behind on maintenance and to let the lender make those payments on your behalf. In return, the lender agrees that the co-op gets paid first in any foreclosure. It protects both sides: the co-op gets a backstop against delinquent maintenance, and the lender gets an early warning of default.
Not every lender offers share loans, and the pool is smaller than for conventional mortgages. Confirm that a lender handles share loans before you get deep into an application. The co-op’s managing agent can usually provide a list of institutions the building has worked with.
Monthly Maintenance and Special Assessments
Co-op shareholders pay a monthly maintenance charge that covers the building’s operating expenses. A significant portion goes toward the corporation’s underlying mortgage, the blanket loan the co-op took out to acquire or refinance the building. Maintenance also includes your proportionate share of real estate taxes, which the corporation pays directly to local authorities, plus building insurance, water, heat, staff salaries, and routine upkeep.
The amount varies based on building size, location, amenities, and how much remains on the underlying mortgage. Buildings that have paid off their mortgage typically have noticeably lower maintenance charges. Your unit’s share allocation determines your percentage of the total, so more shares mean a higher monthly bill.
When the building faces a major expense the operating budget or reserve fund can’t absorb, the board may levy a special assessment. These one-time charges cover things like roof replacement, elevator modernization, or mandated facade repairs. Assessments are allocated the same way as maintenance, proportional to each unit’s shares. They’re mandatory. Shareholders who refuse to pay can have a lien placed against their shares.
The Tax Deductions
One of the financial advantages of co-op ownership is that you can deduct your share of the building’s mortgage interest and real estate taxes on your federal return, just as a traditional homeowner deducts their own mortgage interest and property taxes. Section 216 of the Internal Revenue Code allows tenant-stockholders to deduct their proportionate share of the cooperative corporation’s deductible real estate taxes and interest paid on the corporation’s debt used to acquire or maintain the building and land.2Office of the Law Revision Counsel. 26 USC 216 Deduction of Taxes, Interest, and Business Depreciation by Cooperative Housing Corporation Tenant-Stockholder
The math is straightforward: divide your shares by total shares outstanding, then multiply by the corporation’s total deductible taxes or interest. In practice, the co-op’s accountant provides these figures annually.3IRS. Publication 530 (2025), Tax Information for Homeowners
For the corporation to qualify as a “cooperative housing corporation” eligible for these pass-through deductions, it must meet at least one of three tests: at least 80% of its gross income comes from tenant-stockholders, at least 80% of its total square footage is used by tenant-stockholders, or at least 90% of its expenditures go toward acquiring, maintaining, or caring for the property for the benefit of shareholders.3IRS. Publication 530 (2025), Tax Information for Homeowners Most residential co-ops clear these thresholds easily. Buildings with large commercial spaces on the ground floor sometimes bump up against the limits.
You can also deduct the interest on your personal share loan, treating it the same as home mortgage interest.
House Rules and Occupancy Restrictions
Living in a co-op means accepting a layer of rules that wouldn’t exist in a standalone home and often wouldn’t fly in a condo. The house rules are adopted by the board and enforced through the proprietary lease.
Subletting rules tend to be strict. Many buildings require shareholders to live in their unit for one to two years before they can sublet, and some cap the total number of years you can rent out your apartment or ban subletting altogether. The board typically must approve any subtenant, and the shareholder remains responsible for the subtenant’s behavior and maintenance payments.
Pet policies vary widely. Some buildings allow dogs and cats with size or breed restrictions. Others are entirely pet-free. Renovations require board approval through an alteration agreement, which details the scope of work, requires contractors to carry adequate insurance, and often requires a refundable security deposit to cover potential damage to common areas during construction.
Enforcement has teeth. Repeated violations can result in fines, and in extreme cases the board can move to terminate the proprietary lease, which is the co-op equivalent of eviction. That outcome is rare and requires a legal proceeding, but the possibility shows how much authority the cooperative structure gives to the collective over the individual.
Selling, Flip Taxes, and Passing Shares to Heirs
Closing on a co-op is simpler than a traditional real estate closing since there’s no deed to record with a county office. The seller signs over the stock certificate and proprietary lease to the buyer, the corporation issues new documents in the buyer’s name, and the buyer pays the balance plus administrative fees. The managing agent typically handles the paperwork. Expect two to four weeks from board approval to move-in.
Many buildings charge a transfer fee, commonly called a flip tax, when shares change hands. The seller usually pays it, and the money goes to the cooperative’s reserve fund. The most common approach is a percentage of the sale price, frequently around 1% to 3%. Some buildings calculate the fee as a percentage of the seller’s profit, and others charge a flat dollar amount. The terms are spelled out in the building’s proprietary lease or bylaws, so you’ll know before you buy.
Because co-op shares are personal property, they pass to heirs differently than real estate. Shares held in the deceased shareholder’s name alone typically go through probate, and the executor or administrator needs court authority to transfer or sell them. Shares held jointly with a right of survivorship pass automatically to the surviving co-owner, though the board still must approve the change and reissue the stock certificate. Shares held in a trust can pass to the successor trustee without probate, again subject to board approval. The board’s authority over ownership transfers doesn’t stop at inheritance; a board can require the heir to submit a standard application and meet the building’s financial requirements, and an heir who can’t meet those standards may be forced to sell rather than move in.
On the tax side, inherited co-op shares generally receive a stepped-up basis to fair market value at the date of death, which can significantly reduce capital gains taxes if the apartment is later sold. Whoever handles the estate should know where the original stock certificate and proprietary lease are kept, since replacing lost originals adds delay and expense.