A Delaware promissory note is an arrangement where a borrower borrows a sum of money from a lender with the promise to pay it back by a certain date. The note establishes the amount of the loan, the amount of interest charged, the frequency of payments, any late fees that apply, and collateral (if any).

Any individual, company, or financial institution can issue a promissory note, and they are typically used to loan smaller sums of money. Promissory notes can be secured or unsecured; a secured note means that collateral has to be surrendered by the borrower to ensure the loan is repaid.