SBA 504 vs the Conventional Commercial Mortgage
SBA 504 buys an owner-occupied building with 10% down and a 25-year fixed debenture near 6.5% to 7.25% with no balloon. A conventional commercial mortgage needs 20% to 35% down at 7.5% to 9% and usually carries a 5-to-10-year balloon. Below the 51% owner-occupancy line, 504 is off the table. On a deadline, conventional is usually the only door that closes in time. Everywhere in between, the decision turns on cash, rate certainty, and how long you will hold the property.
Bottom line
Choose SBA 504 when you will occupy at least 51% of the building and want to keep cash in the business: 10% down, a 25-year fixed debenture near 6.5% to 7.25%, and no balloon. Choose a conventional commercial mortgage when you must close inside 45 days, the property is partly leased, you exceed the SBA size standard, or you have the cash and prefer one simpler loan. On a $1.5 million building, 504 preserves roughly $225,000 of cash up front; conventional gives a lower monthly payment but a year-10 balloon to refinance.
Two notes versus one. Different down payment, different balloon, different speed.
The instinct on a building purchase is to chase the lowest rate, and the SBA 504 debenture near 6.95% looks like it has to beat a conventional mortgage at 8%. On the rate alone it does. On the monthly payment it often does not, because the 504 finances 90% of the building while a conventional loan finances 75%. The lower rate sits on more principal. What the 504 actually buys you is two different things: cash kept in the business, and a fixed rate locked for 25 years on 40% of the deal with no balloon.
An SBA 504 loan is two notes on one project. A bank funds 50% as a conventional first mortgage. A Certified Development Company, an SBA-licensed nonprofit, funds 40% as a fixed-rate debenture in second position. You put down 10%. The bank piece prices like any commercial loan; the debenture prices off the monthly bond pool that funds every 504 loan closing that month, which is how it carries a fixed rate for 25 years. The blended cost across both notes usually lands near or slightly below a single conventional rate, and the 10% down is the lowest equity injection in commercial real estate lending.
A conventional commercial mortgage is one loan from one lender, and its defining features are a larger down payment and a balloon. Expect 20% to 35% down and a rate of 7.5% to 9% fixed for 5 to 10 years, after which the full remaining balance comes due and you refinance into the rate environment of that year. The single-lender structure closes faster, carries lighter paperwork, and skips the SBA's occupancy rules and size standards. Those are real advantages when you need speed, when the building is partly leased, or when you have the cash and plan a short hold.
Three questions decide it. First, will your business occupy at least 51% of the building? If not, 504 is off the table and conventional is the only door. Second, how long will you hold the property, and does keeping cash in the business matter? A long hold and a tight cash position both favor the 504's low down payment and no-balloon debenture. Third, is there a deadline? A seller clock, an auction, or a 1031 exchange that demands closing inside 45 days rules out the 60-to-90-day 504 timeline before anything else gets weighed.
How the two loans compare
Twelve dimensions where the SBA 504 loan and a conventional commercial mortgage diverge on the same owner-occupied building. The structural differences explain most of the down payment, balloon, and eligibility gaps on a given deal.
When SBA 504 wins
You will occupy a majority of the building, you plan to hold it, keeping cash matters, the property is special-purpose, or a 25-year fixed rate with no balloon is worth waiting 60 to 90 days for.
- You will occupy at least 51% of the building, you plan to hold it long-term, and keeping cash in the business matters more than the lowest monthly payment. The 10%-down structure leaves $150,000 to $375,000 more working capital on a $1.5 million-to-$2.5 million purchase than a conventional 25%-to-35% down deal.
- You want rate certainty. The 40% SBA debenture locks a fixed rate for 25 years with no balloon, so on nearly half the project your payment does not move regardless of where Prime sits in 2032 or 2036. On a building you intend to own for two decades, eliminating refinance risk on that portion is worth more than a slightly lower opening monthly payment.
- The property is special-purpose (restaurant, hotel, self-storage, car wash, medical facility) where conventional lenders push the down payment to 30% to 35% and shorten the term. The 504 program holds at 15% down on special-purpose property, a gap that frees real cash on exactly the deals where conventional terms are harshest.
- The project bundles ground-up construction, renovation, or expansion, or long-life fixed equipment installed in the building. The 504 program funds all of these inside one structure at the fixed debenture rate, and the construction-to-permanent path is well-trodden through the CDC.
- You comfortably clear the SBA size standard (tangible net worth under $20 million, average net income under $6.5 million) and the 60-to-90-day timeline is workable because the purchase is planned rather than racing a deadline. Patience is the price of admission, and a planned owner-occupied purchase usually has the runway to pay it.
- Total interest over a full 25-year hold matters more than the opening monthly payment. The blended rate across the bank first mortgage and the fixed debenture typically lands at or below a single conventional mortgage rate, and on a held-to-term building that rate advantage compounds even though the 504 finances more of the purchase price.
When a conventional mortgage wins
Speed binds the deal, the building is partly leased or investment, you exceed the SBA size standard, you want cash-out flexibility, or you have the cash and prefer one simpler loan.
- Speed is the binding constraint. A seller deadline, a foreclosure auction, or a 1031 exchange clock that demands closing inside 45 days rules out the 60-to-90-day 504 timeline before rate even enters the conversation. The conventional channel closes in 30 to 60 days on a clean file and faster at a portfolio lender.
- The building is partly leased or pure investment. Anything below 51% owner-occupancy is ineligible for 504 at intake. A mixed-use property where your business fills 40% and tenants fill 60% is a routine conventional file and an automatic 504 decline.
- You exceed the SBA size standard. A business with tangible net worth above $20 million or average net income above $6.5 million over the prior two years does not qualify for the 504 program at all, and conventional is the only commercial real estate door open.
- You have the cash and want a single, simpler loan. A buyer putting 30% down on a building they plan to sell or refinance within seven years often prefers one note, one lender, and no SBA fees, occupancy rules, or annual reporting, even at a higher headline rate. The simplicity has real value when the hold is short.
- You want cash-out beyond owner-occupied business use. A conventional cash-out refinance can pull equity for any purpose the lender allows, including investment, where the 504 refinance program caps cash-out at 20% of appraised value and restricts it to business expenses.
- Your relationship bank offers competitive portfolio terms. A community or regional bank that holds the loan on its own books can sometimes beat the 504 blended rate, add an interest-only period, or negotiate burn-off recourse in a way the SBA's standardized program cannot. When the bank relationship is strong, that offer deserves a real look before defaulting to 504.
Three building purchases, three different answers
Generic buyer profiles based on how each loan gets used in practice. Numbers are illustrative and the arithmetic is yours to re-run. Your actual offers depend on the lender, the property, the credit profile, and current SBA program parameters.
Established service business buying its $1,500,000 office and warehouse
Setup: A 9-year-old commercial HVAC contractor in the Southeast, $4.1 million annual revenue, $620,000 net income, 720 FICO on the majority owner, clean two-year tax returns. The business currently leases its 14,000-square-foot office and warehouse, and the landlord is selling the building for $1,500,000. The business will occupy 100% of the space. The owner has roughly $500,000 of deployable cash and would rather keep most of it in the operating account for equipment and payroll.
SBA 504 path
SBA 504 at 10% down ($150,000). The structure is a $750,000 bank first mortgage at 7.5% fixed for 25 years, plus a $600,000 SBA debenture at 6.95% fixed for 25 years, both fully amortizing. Combined monthly payment is about $10,260. CDC and SBA fees near 2.75% of the debenture finance into the loan rather than draining closing cash. Closes in about 75 days. The owner keeps $350,000 of the $500,000 cash position working in the business.
Conventional mortgage path
Conventional owner-occupied mortgage at 25% down ($375,000). A $1,125,000 loan at 8.0%, amortized over 25 years with a 10-year balloon, runs about $8,680 a month. Closes in about 40 days. The lower monthly is real, but the owner writes a $375,000 check at closing, leaving only $125,000 in the business, and faces a roughly $900,000 balloon at year 10 that must be refinanced at whatever rate the market offers in 2036.
Verdict
It depends on the hold and the cash. The conventional monthly is about $1,580 lower, which is genuine money, and the faster close is a mild plus on a non-urgent purchase. The 504 wins on the two things this owner said matter: it preserves $225,000 more cash up front, and it locks the rate on 40% of the deal for 25 years with no balloon. For a contractor who intends to own this building for two decades and values working capital, 504 is the better fit despite the higher payment. Flip the facts to a buyer planning to sell in six years with cash to spare, and the conventional loan's lower payment and lighter structure win instead.
Retail owner buying an $850,000 mixed-use building on a 1031 deadline
Setup: A boutique fitness studio owner in the Mountain West sells an investment condo and rolls the gain into an $850,000 mixed-use building through a 1031 exchange. The studio will occupy the 3,000-square-foot ground floor, about 45% of the building, while two existing residential tenants occupy the upper floors under leases with 14 months remaining. The 1031 clock requires closing inside the 180-day window, and the identified-property deadline is already 50 days in.
SBA 504 path
Not eligible. The 504 program requires the business to occupy at least 51% of an existing building, and at 45% owner-occupancy this property fails the test at intake regardless of credit or cash. Even if the occupancy cleared, the 60-to-90-day 504 timeline would put the close at risk against the remaining 1031 window.
Conventional mortgage path
Conventional mixed-use commercial mortgage at 30% down ($255,000) on the partly-leased building, with the tenant income actually helping the debt-service-coverage math. A $595,000 loan at 8.25% over a 25-year amortization with a 7-year balloon runs about $4,690 a month before tenant rent is applied. Closes in about 35 days, inside the 1031 window.
Verdict
Conventional wins by default and by design. The 504 program is simply not available on a 45%-occupied building, and the 1031 deadline rules out the slower timeline even in the abstract. This is the cleanest case in the comparison: when the property is majority-leased or the calendar is tight, the conventional channel is not the cheaper option, it is the only option. The tenant rent that disqualifies the building from 504 is the same rent that strengthens the conventional file.
Growing manufacturer buying a $2,600,000 production facility
Setup: An 11-year-old specialty food manufacturer in the Midwest, $7.8 million annual revenue, 695 FICO on the owner, clean financials, expanding out of a leased facility into a $2,600,000 building it will fully occupy and outfit with production lines. The property reads as special-purpose to appraisers because of the food-grade buildout. The business is growing fast and wants every dollar of cash deployed in inventory and new hires for the expansion, not parked in a down payment.
SBA 504 path
SBA 504 at 15% down on the special-purpose property ($390,000). The structure is a $1,300,000 bank first mortgage at 7.75% fixed, plus a $910,000 SBA debenture at 6.95% fixed for 25 years; a manufacturer qualifies for the higher $5.5 million debenture cap, well above this need. Combined monthly is roughly $16,100. Long-life production equipment installed in the building can fold into the same 504 structure. Closes in about 90 days. The 25-year fixed debenture removes refinance risk on 41% of a $2.6 million commitment.
Conventional mortgage path
Conventional commercial mortgage at 35% down on the special-purpose property ($910,000), the steeper equity that conventional lenders attach to food-grade and other single-use buildings. A $1,690,000 loan at 8.75% over a 25-year amortization with a 7-year balloon runs about $13,900 a month. Closes in about 50 days, but the $910,000 down payment pulls more than half the company's deployable cash out of an expansion that needs it, and the year-7 balloon re-prices the whole loan in 2033.
Verdict
504 wins decisively. The down-payment gap alone is $520,000 of cash the manufacturer keeps in the business for the expansion that justified buying the building. The special-purpose property is exactly the case where conventional terms turn harshest (35% down, shorter balloon) and where the 504 program's 15%-down structure is most valuable. The conventional monthly is about $2,200 lower, but on a cash-tight growth-stage company funding inventory and hiring, $520,000 of preserved capital and a no-balloon fixed rate on 41% of the deal are worth far more than the payment difference. The only real cost is the 90-day timeline, which a planned expansion can absorb.
Not sure which structure fits your building?
A two-minute application puts your real estate purchase in front of 300-plus lenders, including SBA Certified Development Companies and conventional commercial mortgage lenders. You see what is actually open on your file, on both paths, before committing to a 90-day 504 process that may not have been the cheaper answer.
See your offersRelated reading
Once you know 504 fits a real estate purchase, the next question is whether to use a 504 or fold the building into a general-purpose 7(a) loan. The blended-rate math and the use-of-proceeds rules decide it.
When the building purchase is part of buying the whole business, the acquisition financing decision sits one level up. How conventional acquisition debt and SBA 7(a) split on equity, term, and goodwill.
The 504 program can fund long-life equipment installed in the building, but a standalone equipment loan is often faster and cheaper below $250K. Where each one wins on an asset purchase.
The full marketplace view across SBA programs, term loans, lines of credit, and equipment financing, with the rate ranges and qualification thresholds for each product.
The credit, time-in-business, debt-service-coverage, and documentation thresholds SBA underwriters actually weight, including what a 504 file needs at intake.
When the production equipment matters more than the building it sits in, a purpose-built equipment loan funds the asset on its own useful-life schedule, often in 1 to 7 days.
Frequently asked questions
Is the SBA 504 rate actually lower than a conventional commercial mortgage?
On the debenture portion, yes; on a blended, all-in basis, it is closer than it looks. The 40% SBA debenture carries a fixed rate near 6.5% to 7.25% in 2026, below a typical conventional owner-occupied rate of 7.5% to 9%. But the 504 finances 90% of the building to conventional's 75%, so the lower rate sits on more principal. The 504's real edge is not a lower monthly payment, which is often higher, but the 10%-down cash preservation and the 25-year fixed, no-balloon structure on the debenture.
How much do I have to put down on an SBA 504 versus a conventional mortgage?
SBA 504 requires 10% down on a standard owner-occupied purchase, 15% on special-purpose property or for a business under two years old, and 20% when both apply. A conventional commercial mortgage requires 20% to 35% down depending on the lender and property type. On a $1.5 million building, that gap runs $150,000 to $375,000 of cash, and it is the single biggest reason owner-occupiers choose 504 over a bank mortgage on the same property.
Can I use an SBA 504 loan for a rental or investment property?
No. The 504 program requires your business to occupy at least 51% of an existing building (60% of new construction). Passive real estate, pure investment property, and majority-leased buildings are ineligible at intake. If your business will occupy less than 51% of the space, or you are buying purely to lease the property out, a conventional commercial mortgage is the only route. The owner-occupancy rule is the hard line between the two products.
What happens at the end of the term? Is there a balloon payment?
This is the structural difference most buyers miss. The 40% SBA debenture fully amortizes over 25 years at a fixed rate with no balloon, so that portion self-liquidates and never re-prices. A conventional commercial mortgage almost always carries a balloon: it amortizes over 20 to 25 years, but the full balance comes due at a 5-to-10-year term, forcing a refinance at whatever rate prevails that year. On a long hold, the 504's no-balloon debenture is a real hedge against a higher-rate decade.
How long does an SBA 504 loan take to close compared to conventional?
SBA 504 runs 60 to 90 days, sometimes past 120 on special-purpose or large projects, because the bank and the CDC underwrite their portions in parallel and both must clear before closing. A conventional commercial mortgage closes in 30 to 60 days on a clean file. The 30-to-60-day gap is why a seller deadline, an auction, or a 1031 exchange clock often pushes a buyer to conventional, even when the 504 terms would be better on a patient timeline.
Can I refinance an existing commercial mortgage with an SBA 504 loan?
Yes, through the 504 Refinance program, made permanent in 2024. The existing conventional debt must be at least two years old, used substantially for 504-eligible purposes (owner-occupied real estate or long-life equipment), and currently performing. You can fold in up to 20% expansion costs and take limited cash-out, capped at 20% of appraised value, for business expenses. For cash-out beyond that, or to refinance investment property, a conventional refinance is the better fit.
Quick Loans Direct is a lending marketplace, not a direct lender. Actual rates, down payment requirements, amortization terms, and approval decisions on SBA 504 and conventional commercial mortgages are made by our lending partners and SBA Certified Development Companies based on their individual underwriting criteria, the property profile, and your business file. Rates and terms may vary by state. California, New York, Virginia, Utah, Georgia, Connecticut, Florida, Kansas, and several other states require specific commercial-financing disclosures that your chosen lender will furnish.
SBA 504 program terms referenced above (the 50/40/10 structure, debenture rates, down payment tiers, owner-occupancy rules, size standards, and the 504 Refinance program) reflect the SBA 504 authority as of mid-2026. Debenture rates, fees, and eligibility are set by SBA notice and change month to month; current program parameters are published at sba.gov. Confirm structure on any specific project with an SBA Certified Development Company before relying on the figures here.
The cost scenarios above use illustrative rates and round figures to show how the structures behave. They are not quotes. Commercial mortgage rates, balloon terms, and down payment requirements vary by lender, property type, loan-to-value, and your business's qualifications, and they change with the rate environment.
This content is for informational purposes only and does not constitute financial, tax, or legal advice. Consult a qualified professional before making business real estate financing decisions. Last reviewed by the Quick Loans Direct editorial team on June 2026.