Most states have usury laws (usually statutes) governing the amount of interest that can be charged on a loan. Usury laws vary from state to state, but the elements of a usury claim are generally: (1) a loan of money; (2) an absolute obligation to repay the principal; and (3) the exaction of a greater compensation than allowed by law for the use of the money by the borrower.

And interest means compensation for the use, forbearance, or detention of money. The term does not include time price differential, regardless of how it is denominated. The term does not include compensation or other amounts that are determined or stated by law not to constitute interest, or that are permitted to be contracted for, charged, or received in addition to interest in connection with an extension of credit.

Service charges, finance charges, and discount points are generally considered interest for purposes of usury. But contingent or uncertain charges are generally not considered interest.

In Oklahoma, usury laws are codified under Title 15 of the Oklahoma Statutes, which governs interest and usury. The legal maximum rate of interest, unless otherwise specifically authorized by law, is 6% per annum when not in writing and 10% per annum when in writing. However, parties can agree to rates as high as 45% per annum for personal loans under $2,000. For loans above this amount, the parties may agree to any interest rate if it is in writing and signed by the party to be charged. The elements of a usury claim in Oklahoma include: (1) the existence of a loan of money; (2) an absolute obligation to repay the principal amount; and (3) the lender charging an interest rate exceeding the limits set by Oklahoma law. Interest is defined as compensation for the use or forbearance of money, but it does not include certain charges such as time price differentials, which are not considered interest under the law. Service charges, finance charges, and discount points are typically treated as interest for the purposes of usury. However, charges that are contingent or uncertain do not generally fall under the definition of interest for usury claims.