SBA 504 vs. Conventional CRE Loan: Which Is Cheaper for a $1M Building? (2026)

Quick answer: For most small-business owners buying a $1M building in June 2026, SBA 504 is the cheaper deal — by $150,000 to $200,000 in lifetime interest for the average borrower, and the lower down payment (10% vs. 20–25%) frees $100,000+ to stay in the business. The exception is a borrower who can get a conventional rate below roughly 7.0% and plans to sell or refinance within 5 years — a narrow profile that most small-business buyers don’t fit.

The SBA 504 vs. conventional question isn’t the same as the general SBA vs. conventional comparison. When you’re specifically buying owner-occupied commercial real estate, the 504 program has a structural advantage that conventional lenders can rarely match: a government-subsidized second mortgage at a fully fixed rate that has run below 6.5% for most of 2025–2026. The question isn’t which program is better in the abstract — it’s whether the rate discount and the lower down payment requirement outweigh the slower timeline, the two-lender closing complexity, and the 10-year prepayment premium.

Here’s the actual math.

Side-by-Side: SBA 504 vs. Conventional CRE

Rates: Prime 6.75% June 2026. SBA 504: 5.95% effective for 25-year debenture. Bank first and conventional at illustrative market rates for owner-occupied CRE. All figures are estimates — get lender-specific quotes.

The Worked $1M Example

Assumptions: Established business (2+ years), existing general-purpose building, strong 680 FICO, standard occupancy.

SBA 504 structure

• Down payment: $100,000 (10%)
• Bank first mortgage: $500,000 at 7.5% fixed, 25yr → $3,695/mo
• SBA second (CDC): $400,000 at 5.95% fixed, 25yr → $2,565/mo
• Combined monthly payment: $6,260
• 25-year total paid: $1,878,000
• Total interest paid: $978,000
• Total cash out (down + payments): $1,978,000

The SBA second’s 5.95% fixed rate is guaranteed for 25 years. If Prime rises to 8.0%, 9.0%, or higher, the SBA second stays at 5.95% — protecting the borrower from the rate exposure that floats on the bank first.

Conventional at 7.75% (strong-credit borrower, 720+ FICO)

• Down payment: $200,000 (20%)
• Single loan: $800,000 at 7.75% fixed, 25yr → $6,042/mo
• 25-year total paid: $1,812,600
• Total interest paid: $1,012,600
• Total cash out (down + payments): $2,012,600

Difference vs. SBA 504: This is the closest case. The conventional borrower’s monthly payment is actually $218 lower ($6,042 vs. $6,260) — they’re financing $800K instead of $900K — yet they commit $100K more upfront and still spend roughly $34,800 more total cash over 25 years. On monthly cash flow alone, the strong-credit conventional deal looks attractive.

The reason 504 still wins comes down to what the lower down payment does. Look at it as a financing decision: the 504 borrower keeps an extra $100,000 in the business and pays just $218/mo more — about $2,600 a year — to do it. That’s effectively borrowing $100K at roughly a 2.6% annual cash cost, because the 504’s blended ~6.9% rate is low enough to offset the larger loan balance. No conventional lender offers working capital that cheap. If that $100,000 funds inventory, equipment, or hiring that returns more than 2.6%, the 504 structure is the better business decision — and the $34,800 total-cash gap understates the advantage.

Conventional at 8.5% (average borrower, 680 FICO)

• Down payment: $200,000 (20%)
• Single loan: $800,000 at 8.5% fixed, 25yr → $6,441/mo
• 25-year total paid: $1,932,300
• Total interest paid: $1,132,300
• Total cash out (down + payments): $2,132,300

Difference vs. SBA 504: $154,500 more in total cash. Here the conventional payment runs $182/mo higher than the 504’s, and that gap stacks on top of the extra $100K down — both compound over 25 years. This is the borrower profile where 504’s rate advantage is clearest.

Conventional at 9.25% (weaker credit or special-use property, 25% down)

• Down payment: $250,000 (25%)
• Single loan: $750,000 at 9.25% fixed, 25yr → $6,423/mo
• 25-year total paid: $1,926,900
• Total interest paid: $1,176,900
• Total cash out (down + payments): $2,176,900

Difference vs. SBA 504: $198,900 more in total cash. Borrowers in this band — limited to conventional because of credit profile or property type — are the strongest candidates for SBA 504 if they qualify.

When Conventional Actually Wins

Despite the math above, conventional CRE lending is the right call in specific situations:

1. Speed is a genuine deal-breaker. SBA 504 takes 90–180 days. If you’re competing with cash buyers, have a 30-day close contingency, or need certainty of close, conventional (or bridge financing) is the only path. An SBA 504 loan you can’t close in time isn’t a better deal — it’s no deal.

2. You plan to sell or refinance within 5 years. The SBA 504 second mortgage carries a 10-year declining prepayment premium. In year 1, the premium can equal roughly the first year’s interest on the debenture ($23,800 on a $400K loan at 5.95%). If you sell or refinance in year 3 or 4, the penalty erodes the rate savings. Conventional loans typically have no prepayment cost.

3. Your conventional rate is genuinely below 7.25%. This happens for borrowers with 720+ FICO, multi-year banking relationships, cross-collateralized deposits, and a simple property with high liquidity. Below ~7.0%, the SBA rate discount narrows enough that the simpler one-loan structure wins.

4. Your project doesn’t qualify for 504. SBA 504 requires 51% owner occupancy on existing buildings (60% on new construction). Investment properties, mixed-use properties where you occupy less than 51%, and businesses that aren’t creditworthy enough for the two-lender underwriting process default to conventional.

The Down Payment Factor People Underestimate

The most common mistake in the 504 vs. conventional analysis is treating the $100,000 down-payment gap as only a cash-flow issue. It’s also a business opportunity cost.

A business owner who puts $200K down on a building has $100K less to invest in revenue-generating assets. A business owner who puts $100K down retains that capital. Even if invested conservatively at a 5% business return, that $100K compounds to $338,000 over 25 years — more than the lifetime interest differential in every scenario above.

This is why SBA 504 was designed with the 10% down requirement: the SBA recognizes that withholding working capital from small businesses to fund real estate equity is often a worse economic outcome than a government-subsidized second mortgage.

Fees: How Much Do They Close the Gap?

SBA 504 has fees conventional loans don’t:

• SBA processing fee: 0.50% of the SBA second = $2,000 on a $400K second
• CDC processing and closing fees: approximately $4,000–$8,000 depending on the CDC and project size (most is financed into the SBA loan, not out-of-pocket)
• Annual CDC servicing fee: 0.209% of the outstanding SBA balance (~$836/yr initially, declining)

Over 25 years, the servicing fee adds roughly $5,000–$8,000 in cumulative fees. Combined with upfront costs, the total fee load might add $12,000–$18,000 compared to a conventional loan’s origination fee of 0.5–1%.

Even accounting for these fees, the rate differential across a $400K balance over 25 years outweighs the fee gap in all but the strongest-credit conventional scenarios.

Decision Framework

Use SBA 504 if:

• You’re an established business buying or building owner-occupied commercial real estate
• You can qualify (660+ FICO, 2+ years in business, the business will occupy 51%+)
• You can wait 90–180 days for closing
• You don’t plan to sell or refinance in the first 5 years
• Conventional rates in your market are above 7.5%

Use conventional CRE if:

• You need to close in under 60 days
• You have a 720+ FICO and a banking relationship that delivers sub-7.25% conventional pricing
• You plan to sell or refinance within 5 years
• The property doesn’t meet 504 occupancy requirements
• You prefer the simplicity of one loan, one lender, one closing

The full SBA 504 eligibility rules also govern use — the program is exclusively for owner-occupied real estate and long-life equipment, and a CDC (Certified Development Company) must certify your project before closing.

Rates and program terms change. Verify current SBA 504 effective rates with a local CDC or the SBA 504 guide at Business Cash Guide before locking anything in. The math above uses June 2026 market rates and is for illustrative comparison only — not a loan offer.