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Seller Financing Contract Terms: What to Put in the Note

By Hans Goldstein · Updated 2026-09-27

A seller financing contract is really three documents: the purchase agreement, the buyer's promissory note, and a security instrument (a deed of trust or mortgage) that lets you take the property back if the buyer stops paying. The terms in those documents decide how safe your money is and when you owe tax. The down payment, rate, balloon date and prepayment terms matter as much to your tax return as the price.

This page explains the terms that protect a seller, how an installment note differs from a straight note and a land contract, and how each term moves your tax. The terms usually enter the purchase contract through a seller financing addendum. This page is educational, not a template: have an attorney who handles seller-financed sales in the property's state draft the documents. To see how different terms change your payments and tax by year, use the seller financing calculator.

The documents

Document What it does Who signs
Purchase agreement Sets price, down payment and financing terms, and the conditions to close Buyer and seller
Promissory note The buyer's promise to pay: amount, rate, schedule, late fees, default terms Buyer (and any co-signers)
Deed of trust or mortgage Secures the note with the property, so you can foreclose on default Buyer, recorded against the property
Personal guaranty (optional) Makes another person liable if the buyer does not pay Guarantor
Title and escrow instructions Records the deed and your lien, sets up any tax and insurance handling Escrow or title company

For tax purposes, the buyer's note (or deed of trust, land contract or mortgage) is your "installment obligation." IRS Pub. 537 lists all of these as forms the buyer's obligation can take.

Terms that protect the seller

Down payment. The single biggest protection. A larger down payment gives the buyer equity to lose and gives you a cushion if you have to take the property back. It also raises your year-one taxable gain, since the down payment carries the same gross profit percentage as every later payment.

Interest rate. For tax, the rate should be at least the applicable federal rate for the note's term, or part of your principal is recharacterized as interest (§§483, 1274). Above that floor, the rate is a business decision. See the AFR minimum.

Term and amortization. How long the buyer has to pay, and whether the payments fully pay off the loan by the end (fully amortizing) or leave a large balance due (a balloon).

Balloon date. A balloon lets the buyer keep payments low and refinance later. It concentrates your gain in the balloon year. See the example below and the seller financing balloon payment guide.

Prepayment terms. A buyer who refinances pays you off early, and all the remaining gain is taxed in that year. A commercial note can include a prepayment lockout or premium. A residential note to an owner-occupant may be limited by consumer lending rules; ask your attorney.

Late fees and default. Define late charges, a grace period, what counts as default (missed payments, unpaid property tax, lapsed insurance, unapproved transfer), and your remedies.

Due-on-sale. If the buyer sells or transfers the property, the full balance comes due. This keeps a stranger from taking over your note without your consent. It also means a resale by the buyer usually ends your installment schedule and brings the remaining gain into that year.

Insurance and property tax. Require hazard insurance naming you as loss payee or mortgagee, and proof that property taxes are paid. Some sellers collect monthly escrow for both so a lapse cannot put a tax lien ahead of them.

Personal guaranty. If the buyer is an LLC or corporation, a personal guaranty from the owners puts their personal assets behind the note. Whether you can actually collect beyond the property depends on state law (see the California note below).

Lien position. A first-position deed of trust is far safer than a second behind a bank loan. If you carry back a second, your lien can be wiped out if the bank forecloses. See seller carry back risks.

Financial information. For commercial property, require annual financial statements and rent rolls, so you see trouble before payments stop.

Installment note vs straight note

Installment note Straight note
Payments Principal (and usually interest) in regular installments Interest only, or nothing, until maturity
Principal Paid down over time All due at the end
Seller's credit exposure Shrinks each year Full balance until the end
Seller's gain for tax Spread as principal is paid Nearly all in the maturity year

A straight note still qualifies for the installment method, because at least one payment arrives after the year of sale. But a straight note with a large principal due in one year puts most of the gain back into one year's brackets, which undoes much of the point of spreading it.

Land contract vs note and deed of trust

In a land contract (also called a contract for deed or installment land contract), the seller keeps legal title and the buyer gets possession and equitable ownership. Title passes when the buyer finishes paying. In a note and deed of trust, the buyer gets title at closing, and the seller holds a lien. Full comparison: land contract vs seller financing.

For federal tax, the two are handled much the same way:

The practical differences are legal: how you remove a defaulting buyer, what notice is required, and what rights the buyer has. Those rules vary by state, which is one more reason to use a local attorney.

How terms change your tax

Simple example. Married filing jointly, $100,000 of other ordinary income each year, standard deduction, 2026 federal brackets held flat (Rev. Proc. 2025-32). The note's interest is included on the return as ordinary income. The gain is long-term capital gain on land (no depreciation). Federal income tax plus the 3.8% net investment income tax. The down payment is ignored because it is taxed the same way in both versions.

A seller carries a $400,000 note on land with a 60% gross profit percentage. Every principal dollar carries 60 cents of gain, $240,000 in total. Two versions of the note:

Balloon version:

Year Principal received Gain (60%) Federal tax on the gain
1 $4,063 $2,438 $0
2 $4,357 $2,614 $0
3 $4,672 $2,803 $0
4 $5,010 $3,006 $0
5 (with balloon) $381,898 $229,139 $37,707
Total $400,000 $240,000 $37,707

Level version: $24,000 of gain each year for 10 years. Total federal tax on the gain: $13,320, highest in year 1 ($3,135) and falling as interest income declines.

Same note, same rate, same total gain. The balloon version costs about $24,000 more in federal tax in this simple example because it stacks $229,139 of gain into one year, pushing part of it into the 15% band and part over the 3.8% line. The level version keeps most of the total gain in the 0% band (about $151,000 of the $240,000), and none of it crosses the 3.8% line.

Other terms that move tax:

California: why remedies matter

State law decides what "secured" means in practice. In California, for example, a seller who carries back part of the purchase price on a deed of trust generally cannot get a deficiency judgment against the buyer (Code Civ. Proc. §580b). If the property is worth less than the balance owed, the property is all you get, which makes the down payment and lien position more important than any clause about personal liability. Other states have different rules; your attorney should explain yours.

Checklist

Bottom line

The contract terms are your tax plan. The down payment sets your year-one gain, the rate floor protects the character of your gain, and the balloon and prepayment terms decide whether the gain stays spread or lands in one year. Negotiate the terms with the tax effect in view, and have a local attorney draft the documents rather than a template. For the full tax picture, read seller financing taxes and what happens on default or early payoff.

Questions to ask your CPA

  1. What will my gross profit percentage be, and how much gain does the down payment trigger in year one?
  2. What minimum interest rate does the note need, and which AFR applies?
  3. How much more tax would a 5-year balloon cost me than a 10-year level schedule?
  4. If the buyer prepays or sells, what will I owe that year?
  5. How are the interest and gain reported each year, and do I need the buyer's SSN?
  6. If I have to take the property back, how will §1038 treat it?

Run your own numbers. Compare a cash sale, seller financing and a structured installment sale side by side, free.

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Educational only, not tax, legal or investment advice. Examples are illustrative. Have your CPA or tax attorney review your facts before you act. Hans Goldstein is a licensed insurance agent (CA Insurance License #4273294) and is not a CPA or attorney. He is paid a commission only if a structured installment sale is funded; seller financing pays him nothing. Disclosures.