Topic Terms

What is a Promissory Note?

A promissory note is a written, legally binding promise by one party (the maker) to pay a specified amount of money to another party (the payee), under specified terms including interest rate and repayment schedule.

A promissory note is a written legal instrument in which one party — the maker (or promisor) — makes an unconditional written promise to pay a definite sum of money to another party — the payee — either on demand or at a specified future date. It is signed by the maker and constitutes a binding financial obligation enforceable in court.

Promissory notes are foundational documents in lending: every mortgage, student loan, and most personal and business loans are documented with a promissory note.

Required Elements of a Promissory Note

For a promissory note to be legally enforceable, it typically must include:

  • Names of parties — Identification of the maker (borrower) and payee (lender)
  • Principal amount — The exact sum being borrowed
  • Interest rate — The rate at which interest accrues, if any (APR or simple interest)
  • Repayment terms — Payment schedule (monthly, lump sum, on demand)
  • Maturity date — When the full balance must be paid
  • Consequences of default — What happens if the maker fails to pay
  • Signature of the maker — Required; payee signature is optional in most jurisdictions

If any essential element is missing, the note may be unenforceable or treated as an informal IOU rather than a negotiable instrument.

Types of Promissory Notes

Demand promissory note: The payee can demand repayment at any time. There is no fixed maturity date. Common in informal personal loans.

Installment promissory note: Repayment occurs in regular installments (monthly payments) over a set period — the structure used in mortgages and auto loans.

Interest-bearing promissory note: Specifies a stated interest rate. The maker owes the principal plus accumulated interest.

Non-interest-bearing (zero-interest) promissory note: No stated interest rate; maker repays only the principal. Common in family loans or certain business contexts — though the IRS may impute interest if rates are below the Applicable Federal Rate (AFR).

Secured vs. unsecured:

  • Secured: Backed by collateral (e.g., a mortgage note is secured by the property). If the maker defaults, the lender can seize the collateral.
  • Unsecured: No collateral. The lender's only remedy on default is a lawsuit to collect the judgment.

Promissory Notes in Common Transactions

Transaction Role of Promissory Note
Mortgage Defines the personal repayment obligation; separate from the deed of trust
Student loans Federal promissory note (MPN) signed at origination
Personal loan Formalizes the repayment terms between individuals
Small business loan Primary documentation of the debt obligation
Seller financing Documents the payment terms when a seller finances the buyer directly

Negotiable Instrument Status

Under the Uniform Commercial Code (UCC), a promissory note may qualify as a negotiable instrument if it is unconditional, payable in a fixed amount of money, payable to order or bearer, and signed by the maker. A negotiable promissory note can be transferred to a third party — which is why your mortgage lender may sell your loan to another bank; the promissory note travels with the sale.

Promissory Note vs. IOU vs. Loan Agreement

Document Legal Strength Detail Level
Promissory note Enforceable legal instrument Moderate
IOU Informal acknowledgment of debt Minimal
Loan agreement Detailed contract with all terms Highest

A promissory note is stronger than an IOU but less comprehensive than a full loan agreement — it documents the core payment obligation without all the ancillary provisions of a complete contract. For larger loans, attorneys often create both.