Seller Financing Calculator
Structure a private mortgage note. Calculate monthly payments based on amortization, and determine the balloon payment due if the loan term is shorter.
| # | Date | Payment | Principal | Interest | Balance |
|---|---|---|---|---|---|
| Calculate to see schedule | |||||
How to Use the Seller Financing Calculator
No spreadsheet, no lender, no guesswork. Follow these five steps and you’ll have a complete, legally-usable note summary — including the exact balloon payment due at term end — in under a minute.
Enter the Sale Price & Down Payment
Type in the agreed purchase price of the property. Then enter the down payment — the amount the buyer pays upfront in cash at closing. The calculator instantly shows the net loan amount the seller will finance. Use the percentage slider to quickly model different down payment scenarios, from 5% to 30%.
Set the Interest Rate
Enter the annual interest rate agreed between buyer and seller. Seller-financed notes typically carry rates 1–3 points above current conventional mortgage rates, reflecting the added risk the seller takes on as lender. Use the rate slider to instantly see how different rates affect the monthly payment — a powerful negotiating tool at the table.
Choose Your Amortization Period
The amortization period determines the monthly payment size — a 30-year amortization produces a lower payment than a 15-year on the same principal. Most seller-financed deals use a 30-year amortization to keep payments manageable. Enter your chosen period here, then move to the balloon term in the next step.
Set the Balloon Due Date (Term)
Enter how many years until the full remaining balance is due — typically 3, 5, or 7 years in seller financing. The calculator will automatically compute the exact balloon payment amount owed at the end of this term, based on the amortization schedule. Both parties need this figure before signing any note.
Calculate & Download Your Note Summary
Click “Calculate Note” to instantly see the full monthly P&I payment, total interest earned over the term, principal paid down, balloon amount due, and a complete amortization schedule. Click “Download PDF” to generate a professional note summary you can share with your real estate attorney, the other party, or your accountant.
What This Calculator Shows You
Seller financing involves more moving parts than a conventional mortgage. This calculator surfaces every number that matters to both parties — before you put anything in writing.
Monthly P&I Payment
Calculated using the standard fixed-rate amortization formula on your net loan amount (sale price minus down payment). This is the same math your bank uses — the monthly payment is based entirely on the amortization period you set, not the balloon term. This number appears in your promissory note.
Total Interest Earned Over Term
The total amount of interest the seller will collect from the buyer across all monthly payments within the balloon term. This is taxable ordinary income to the seller in the year received and is a key figure for sellers evaluating whether owner financing outperforms a lump-sum conventional sale.
Principal Paid Down Over Term
How much of the original loan balance the buyer will have amortized away by the balloon date. Because early payments are heavily weighted toward interest, the principal paydown during a short balloon term is often less than buyers expect — making the balloon figure significantly larger than the original loan amount minus payments made.
Balloon Payment Due at Term End
The exact lump-sum balance the buyer must pay (or refinance) when the balloon date arrives. This is the most critical number in any seller-financed deal — if the buyer cannot refinance or sell at term end, both parties face a difficult situation. Always model this figure before agreeing to terms.
Balance Trajectory Chart
A visual line chart showing how the outstanding loan balance declines month by month from closing to the balloon date. This makes it immediately clear to both parties how much equity the buyer will have built — and how large the balloon payment will be — before the term ends.
Full Amortization Schedule
A complete month-by-month table showing payment number, date, total payment, principal portion, interest portion, and remaining balance — for every payment up to the balloon date. Expand the accordion in the results panel to view it on screen, or download the PDF to share the complete schedule with all parties.
Key Benchmarks Every Seller-Financed Deal Should Know
Common Seller Financing Structures This Calculator Supports
“Seller financing” is an umbrella term covering several distinct deal structures. Each has different legal implications, risk profiles, and cash-flow outcomes. Regardless of which structure you use, the payment math is identical — making this calculator useful for all of them.
The seller holds a promissory note secured by a deed of trust or mortgage. The buyer takes legal title at closing, makes monthly P&I payments directly to the seller, and must pay the full balloon balance at term end — typically by refinancing with a bank. This is the structure this calculator models exactly. A real estate attorney should draft the note and deed of trust.
The seller retains legal title to the property until the buyer makes enough payments or pays off the balloon. The buyer holds “equitable title” — the right to use and eventually own the property. Payment math is identical to standard owner financing. Laws governing land contracts vary significantly by state; some states heavily favor the buyer, others the seller. Legal counsel is essential.
The seller has an existing mortgage they continue to pay. The buyer’s new note “wraps around” that existing loan — the buyer pays the seller a higher rate on the full purchase price, and the seller uses part of those proceeds to cover the underlying mortgage payment. To model this: enter only the equity portion as the loan amount, or the full purchase price with the rate set to your wraparound rate. Caution: most existing mortgages contain due-on-sale clauses that technically prohibit this without lender consent.
The buyer obtains a conventional first mortgage from a bank for the majority of the price, and the seller carries a second note for part of the remaining balance — effectively replacing the down payment the buyer can’t fully fund. To model this: enter only the seller-financed portion (e.g., $40,000) as the sale price with no down payment, and use the agreed rate and balloon term. Note that some first-lien lenders prohibit seller seconds — confirm with the primary lender.
The buyer leases the property with the option (not obligation) to purchase at a preset price within a defined window. A portion of each monthly rent payment may be credited toward the purchase price. Use this calculator to model the projected purchase financing at the end of the lease period — enter the agreed purchase price, expected down payment, and anticipated interest rate at the option exercise date to estimate future monthly payments.
Seller Financing vs. Conventional Mortgage — Key Differences
Understanding how seller financing differs from a bank loan helps both buyer and seller negotiate better terms — and avoid surprises at the closing table.
| Feature | Seller Financing | Conventional Mortgage |
|---|---|---|
| Who provides the loan? | The property seller | Bank, credit union, or lender |
| Credit score requirement | Negotiable — set by seller | Typically 620+ (conventional) or 580+ (FHA) |
| Closing speed | Days to 2–3 weeks | 30–60 days on average |
| Origination fees & points | None required | 0.5%–2% of loan amount typical |
| PMI requirement | None — never required | Required if down payment < 20% |
| Interest rate | Typically 1–3% above conventional | Set by market; often lower |
| Loan term structure | Short balloon (3–10 yrs), long amortization | Full term (15 or 30 years, no balloon) |
| Balloon payment risk | Yes — buyer must refinance at term end | None on standard fixed-rate loans |
| Appraisal requirement | Negotiable between parties | Required by lender in almost all cases |
| Seller tax treatment | Installment sale (spread capital gains over time) | Full capital gain in year of sale |
| Note can be sold? | Yes — at a discount to face value | N/A — bank retains or sells on secondary market |
Important: Interest rate, down payment, balloon term, and all other conditions in a seller-financed deal are entirely negotiable between buyer and seller. There is no regulatory minimum or maximum — only the IRS Applicable Federal Rate (AFR) sets a floor below which the IRS will impute interest for tax purposes. Consult a CPA before setting a rate below current AFR levels.
How Different Parties Use This Calculator
The numbers that matter most — and the questions you need answered — depend entirely on which side of the table you’re sitting on.
Property Sellers
Acting as the lenderYou’re choosing to carry the note instead of cashing out conventionally. Your priorities are yield, security, and exit strategy. This calculator shows you exactly how much interest income you’ll collect, when you’ll receive the balloon, and what the note is worth as a sellable asset.
- Model multiple rate scenarios to find your target yield
- Compare a 5-year vs. 7-year balloon to evaluate liquidity timing
- Higher down payment = lower LTV = safer position if buyer defaults
- Download the PDF to share with your accountant for installment sale planning
- Run the numbers before listing — seller financing attracts more buyers
Home Buyers
Bypassing traditional lendingYou may not qualify for a conventional mortgage today — or the deal simply makes more sense with seller financing. Your top concern is affordability now, and your ability to refinance before the balloon hits. Use this calculator to stress-test both scenarios.
- Compare the monthly payment vs. a conventional loan at the same price
- Understand exactly what you’ll owe at balloon date — plan your refinance early
- A 30-year amortization gives you the lowest monthly payment regardless of balloon term
- Download the PDF to present to a future conventional lender as your payment history baseline
- Use the amortization table to track your equity growth month by month
Real Estate Investors
Creative finance deal-makersWhether you’re buying with seller financing, creating a note on a flip, or evaluating a note for purchase, the math is the same. This calculator is your rapid deal-analysis tool — model any scenario in seconds before you make an offer or a commitment.
- Model seller second notes by entering only the carried-back amount as the sale price
- Evaluate note purchases: use the balloon as the payoff you’ll receive
- Compare 3-year vs. 5-year vs. 7-year balloon exit timelines
- The PDF report is a clean deal-analysis document for your investor partners
- Stack multiple scenarios using different rates and amortization periods
7 Things to Know Before Structuring a Seller-Financed Note
Seller financing can be a powerful tool for buyers, sellers, and investors — but only when structured carefully. These practical considerations can save both parties thousands of dollars and prevent serious legal complications.
Always Use a Real Estate Attorney to Draft the Documents
A seller-financed transaction involves legally binding instruments — a promissory note and a deed of trust or mortgage — that must be properly drafted and recorded to be enforceable. Using a template from the internet or a title company form without legal review is a significant risk. The cost of a real estate attorney ($500–$2,000) is trivial compared to the cost of a defective note that can’t be enforced or sold.
Record the Deed of Trust or Mortgage with the County
The seller’s security interest in the property must be recorded in the public records of the county where the property is located. Recording establishes the seller’s priority lien position and protects against the buyer encumbering the property with additional debt or selling the property without paying off the note. Failure to record puts the seller’s entire investment at legal risk.
Require the Buyer to Maintain Homeowners Insurance
As the holder of the note, the seller has a financial interest in the property being insured. Require the buyer to carry a homeowners policy with the seller listed as an additional insured or mortgagee. This ensures that if the property is damaged or destroyed, the insurance payout goes to satisfy the note balance first — protecting the seller’s collateral.
Understand the IRS Applicable Federal Rate (AFR) Before Setting Your Rate
The IRS publishes monthly AFRs — the minimum interest rate that must be charged on private loans to avoid the transaction being treated as a gift for tax purposes. If the note’s stated interest rate is below the AFR, the IRS will impute interest at the AFR regardless, which creates phantom income for the seller and a deduction for the buyer. Check the current AFR at IRS.gov before finalizing your rate.
Include a Due-on-Sale Clause in the Note
A due-on-sale clause (also called an acceleration clause) requires the buyer to pay the full remaining balance if they sell or transfer the property without the seller’s consent. Without this clause, the buyer could sell the property to a third party and leave the original seller’s note outstanding against the new buyer’s property — a situation most sellers want to avoid entirely.
Model the Balloon Payment Early — and Have a Plan B
The most common failure point in seller-financed deals is the balloon date — the buyer can’t refinance (market rates spiked, credit didn’t improve, property didn’t appraise) and can’t pay the balloon. Both parties should agree upfront on what happens if this occurs: extension with renegotiated terms, deed-in-lieu of foreclosure, or a structured payoff plan. Use this calculator to model both the original scenario and any extension scenarios before you sign.
Know That Your Note Is a Sellable Asset
A properly drafted, recorded promissory note secured by real estate can be sold to a note buyer — an individual or institutional investor who purchases performing private notes. The note will sell at a discount to face value (typically 10–30%, depending on rate, LTV, payment history, and market conditions). If you need liquidity before the balloon date, selling the note outright or selling a partial interest in the payments are both legitimate exit strategies worth evaluating when you structure the deal.
Seller Financing Calculator FAQ
Straightforward answers to the questions buyers, sellers, and investors ask most.
Important disclaimer: All calculations provided by this tool are for educational and estimation purposes only and do not constitute financial, legal, or real estate advice. Results are based entirely on the inputs you provide and standard fixed-rate amortization mathematics. Actual note terms, interest rates, tax implications, and legal enforceability will vary based on state law, local regulations, lender policies, and the specifics of your transaction. The IRS Applicable Federal Rate (AFR) sets a minimum interest rate for private loans — confirm current AFR levels at IRS.gov before finalizing any note. Seller financing transactions should always be reviewed and documented by a licensed real estate attorney in your state. HomeExpertly is not a lender, broker, financial advisor, or attorney.