Mixed use condo financing turns on one number: the share of the project's square footage used for non-residential purposes. Fannie Mae caps it at 35%. FHA uses the same 35% standard with a discretionary exception above it. Cross the line and the project is ineligible, which means no conventional loan on any unit in the building, not just the loft above the dentist's office.
The number is simple. Finding it is not. Management companies estimate it on questionnaires, and the document that actually settles the question is the recorded declaration. Here is how the calculation works, where commercial space is defined in the documents, and what to verify before the file reaches underwriting.
The short version
- Fannie Mae's limit: space used for nonresidential or commercial purposes may not exceed 35% of the project.
- The math is non-residential square footage divided by total project square footage.
- Rental apartments and hotel rooms count as non-residential. HOA-owned amenity space reserved for residents does not. Commercial parking facilities can be excluded.
- FHA also uses 35%, with exceptions up to 49% where the residential character of the project is maintained.
- The declaration defines the commercial units. The questionnaire reports someone's estimate of them.
The one number mixed use condo financing turns on
Fannie Mae's Selling Guide is direct about it. In the ineligible projects section, "the total space that is used for nonresidential or commercial purposes may not exceed 35%." Above that, the project is ineligible under B4-2.1-03, and the ineligibility attaches to the project rather than to the unit.
The calculation is a ratio: total non-residential square footage divided by the total square footage of the project or building. Classification is what complicates it, not arithmetic.
Counted as non-residential: retail, restaurants, offices, and space owned by private parties outside the association. Rental apartments and hotels also count, even though people live in them, because the test measures residential ownership rather than residential use. A building with 60 condo units stacked above 40 leased apartments sits closer to the limit than anyone in the deal expects.
Not counted: amenity space that is residential in nature, designated for the exclusive use of the residential unit owners, and owned by the unit owners or the HOA. The gym, the club room, and the roof deck belong to the owners, so they are not commercial. Fannie's guide also allows commercial parking facilities to be excluded, which matters in urban buildings where a parking deck dominates the floor plate.
One correction worth making, because the stale figure still circulates. You will find lender pages citing 25% as the ceiling. The current Selling Guide language is 35%. A loan officer screening against the older number may be declining projects that are eligible.
Commercial percentage is also a separate test from hotel operation. A project run as commercial lodging is ineligible on its own terms, which we covered in condotel financing. A building can sit well under 35% commercial and still fail as a condotel, or run 40% commercial with no hospitality operation in it anywhere. Full review tests both.
Where commercial space is defined in the condo documents
Start with the recorded declaration, because it is the instrument that creates the units. If a building contains separately owned commercial space, the declaration has to say so, and it usually says so in one of four places.
The definitions article. Look for a defined term such as Commercial Unit, Non-Residential Unit, or Retail Unit sitting alongside Residential Unit. A declaration that defines two classes of unit is telling you the commercial space exists inside the same condominium regime as the homes.
The unit schedule exhibit. Most declarations attach an exhibit listing every unit with its square footage and its undivided percentage interest in the common elements. That table is the closest thing to a primary source for the ratio. Total the non-residential square footage, divide by the project total, and the number has a recorded document behind it instead of a phone call.
The assessment article. Commercial units are often assessed on a different basis than residential units, sometimes with a separate budget category and separate maintenance obligations. A distinct commercial assessment formula confirms separately owned commercial space.
The voting article. Class A residential and Class B commercial voting structures are common, as are provisions giving the commercial owner consent rights over specific amendments. Both tell you the commercial component is a party to the governance, not a tenant.
The plat or plans attached to the declaration show the footprint. Then read the amendments. A building that converted association-owned amenity space into leased retail did it by amendment, and the original declaration will not mention it.
Why the questionnaire and the declaration often disagree
The condo questionnaire asks for the percentage of the project used for non-residential purposes. Someone at the management company answers, often from memory, sometimes by copying a prior questionnaire that was itself a guess. Underwriting then treats the answer as verified fact.
Three structures make the honest answer genuinely hard to give.
The retail sits outside the residential HOA. In many newer buildings the commercial component is its own condominium regime or its own tax parcel, connected to the residential association only through a master declaration or a reciprocal easement agreement. The residential manager may reasonably answer 0%, because within that regime it is 0%. Whether the "project" means the residential regime or the whole building depends on how the documents draw the boundary.
The association leases space it owns. When the HOA owns the ground-floor suite and leases it to a dentist, the ownership test and the use test point in opposite directions. The exclusion requires the space to be residential in nature and reserved for resident use. A leased commercial suite is neither.
Apartments in the stack. Partial conversions leave a rental floor or two in place. Those units count as non-residential even though they are dwellings, and no manager thinks to include them when answering a question about commercial space.
If the percentage on the questionnaire came back suspiciously round, it was estimated. Ask for the unit schedule and run the arithmetic yourself.
What happens when the project is over the limit
Above the 35% line the conventional path closes for every unit in the building, which is one of the standard triggers that makes a project non-warrantable. What remains is portfolio and non-QM lending, where the bank holds the loan on its own books and applies its own project standards. Those loans exist and they close. They also tend to require a larger down payment and price higher than a conforming loan.
FHA applies the same 35% standard with a release valve. FHA may grant an exception permitting commercial space above 35% and up to 49% where the residential character of the project is maintained, and HUD holds discretion to move the limit within a 25% to 55% band. The NAR summary of the FHA condominium rule lays out those figures, including the 35% maximum that applies to single-unit approval. An exception is documented, not asserted.
The consequence the borrower feels later is resale. A project financeable only through portfolio lenders has a smaller buyer pool at every future sale, and that shows up in price. It can still be a sound purchase at the right number, with the constraint priced in at the front of the deal rather than discovered in week three.
The outcome worth avoiding entirely is a full appraisal and a full project review ordered on a building that five minutes with the declaration would have flagged.
What ClearHOA pulls from the declaration
Upload the declaration or CC&Rs, the bylaws, the rules and regulations, the plat exhibits, or the HOA addendum, and ClearHOA returns the project structure in plain English with the section reference attached to each item: whether the declaration creates commercial or non-residential units, the unit schedule and square footage allocation behind the percentage, separate commercial assessment and voting classes, master association and separate-regime structures, and the other document-side flags a full review will test. It reads whichever documents you have rather than one required form, and it returns in under 90 seconds.
Frequently asked questions
Can you get an FHA loan on a mixed-use condo?
Yes, if non-residential space stays at or under 35% of the project's total floor area. FHA may grant an exception above 35% and up to 49% where the residential character of the project is maintained, supported by documentation. Single-unit approval carries the same 35% maximum.
How is commercial space percentage calculated for a condo?
Total non-residential square footage divided by the total square footage of the project or building. The unit schedule exhibit attached to the declaration usually lists square footage per unit, which lets you compute the ratio from a recorded document rather than from an estimate.
Does a parking garage count as commercial space?
Under Fannie Mae's guideline, commercial parking facilities can be excluded from the calculation. Resident parking owned by the association or assigned to units as limited common elements is not commercial space at all. How the declaration classifies the parking settles it.
Do apartments in the building count as commercial space?
Yes. Rental apartments and hotel rooms count as non-residential under Fannie Mae's guideline even though they are dwellings, because the test measures residential ownership rather than residential use. Partial conversions with a floor of leased apartments often sit closer to the limit than the parties realize.
Is a condo above a restaurant harder to finance?
Not by itself. A ground-floor restaurant in a 200-unit tower is a rounding error against the 35% limit. The financing problem shows up when non-residential space is a large share of the floor plate, or when the retail component sits in a separate regime that leaves the project boundary ambiguous.
If a project questionnaire lands on your desk with a commercial-space percentage that reads like a guess, run the declaration through ClearHOA before you order the full review. You will get the unit classes, the square footage allocation, and the master-association structure with section citations attached. Enough to document the file or decline it the same afternoon.