SBA Equity Requirement Calculator
Most people planning an SBA 504 project assume they need 10% down. Two things can push that to 15% or 20%, and both of them are decided before anyone looks at your credit: whether the business is a year old or less, and whether your building is on SBA's Limited or Special Purpose Property list. On a $1.2 million project that is the difference between $120,000 and $240,000 of your own money. This calculator works it out from the current rulebook.
Where these numbers come from
Every figure is from SOP 50 10 8.1, "Technical Policy Updates effective 10.1.2026", which is the version currently in force. Nothing here is our estimate.
The SOP sets out the typical 504 structures as follows, reproduced from its own table:
| Party | Standard | New Business or Limited/Special Purpose | Both |
|---|---|---|---|
| Third Party Lender | 50% | 50% | 50% |
| CDC / SBA debenture | 40% | 35% | 30% |
| Borrower | 10% | 15% | 20% |
In the SOP's own words, a business with a Limited or Special Purpose Property "Must contribute at least 15%, in which case the Debenture will finance no more than 35% of the Project", and "Must contribute at least 20%, if the Project involves a new business". It adds: "If a Project will finance both a New Business and a Limited or Special Purpose Property, the Applicant must contribute at least 20% of the Project cost."
What counts as a new business
This catches experienced operators constantly, because the test is about the business and not about you:
SBA considers a business to be a "start-up" for the purpose of determining equity injection requirements if it has been in operation (i.e., generating revenue from intended operations) for 1 year or less.
Thirty years in the industry does not exempt a company formed last month.
The property list, and the trap in it
These are the property types SOP 50 10 8.1 names as Limited or Special Purpose, verbatim:
Amusement parks; Bowling alleys; Car wash businesses; Cemeteries; Cold storage facilities where more than 50% of total square footage is equipped for refrigeration; Dormitories; Farms, including livestock and dairy facilities; Funeral homes with crematoriums; Gas stations; Golf courses; Hospitals, surgery centers, urgent care centers, and other health or medical facilities; Hotels, motels, and other lodging facilities; Marinas; Mines; Nursing homes, including assisted living facilities; Oil wells; Quarries, including gravel pits; Railroads; Sanitary landfills; Service centers (e.g., oil and lube, brake, or transmission centers) with pits and in-ground lifts; Sports arenas; Swimming pools; Tennis clubs; Theaters and auditoriums; and Wineries.
Not being on that list is not a safe harbour. The SOP says the list "is not intended to be all-inclusive" and that SBA "may determine that other properties meet the Limited or Special Purpose Property definition". It also puts the question squarely on your CDC:
CDCs must address whether the Project Property is Limited or Special Purpose in their credit memorandum and include an explanation of their conclusion.
So somebody writes down an answer either way. If your property type is not named, ask which way they will call it before you budget the 10%. A veterinary hospital is the clearest example: the word "veterinary" appears nowhere in the SOP, but "other health or medical facilities" is right there in the list.
If you are using 7(a) rather than 504
SBA considers an equity injection (Applicant contribution) of at least 10 percent of the total project costs (all costs required to become operational, regardless of the source of funds, except for lines of credit and 504 loans) to be necessary for a Start-Up Business to operate on a sound financial basis.
The parenthesis is the part that catches people. The base is all costs required to become operational, not the loan amount, and explicitly regardless of who funds them. Equipment on a vendor line, your own savings, a friend's money: all inside the base. Only lines of credit and 504 loans are excluded.
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title="SBA equity requirement calculator"
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We write the SBA business plans and financial models these projects are approved on, including the project cost build-up the equity injection is measured against. Fees are fixed and published, and we never charge a percentage of anything you borrow or raise.
Frequently asked questions
Is the SBA 504 down payment always 10%?
No. 10% is the standard structure. It rises to at least 15% if the business is new or the property is Limited or Special Purpose, and to at least 20% if both apply.
What makes a property "special purpose" for SBA?
SOP 50 10 8.1 names 25 categories, listed in full above. The list is expressly not all-inclusive, and your CDC must reach and record a conclusion either way in its credit memorandum.
I have run businesses for years. Am I still a start-up?
If the borrowing business has been generating revenue from its intended operations for one year or less, yes. The SOP's test is the age of the business, not the experience of its owner.
Is the 10% on a 7(a) start-up loan measured against the loan?
No, against total project cost: all costs required to become operational, regardless of the source of funds, excluding lines of credit and 504 loans. That is usually a larger number than the loan.
Can I use this calculator on my own website?
Yes. Copy the embed code above. It is free, carries no tracking, and we do not ask for anything in return.
This calculator reflects SBA SOP 50 10 8.1 as at 4 October 2026. It is general information, not lending, legal or tax advice, and it is not a commitment to lend. SBA reissues policy regularly and lenders apply their own credit policies on top of it. Your CDC and lender make the determination. Confirm every figure with them before you commit capital.