A surety bond is a contract between at least three parties: (i) the principal, (ii) the obligee, and (iii) the surety. Through this agreement, the surety agrees to make the obligee whole (usually by payment of money) if the principal defaults in its performance of its promise to the obligee. The contract is formed so as to induce the obligee to contract with the principal, i.e., to demonstrate the credibility of the principal.
Suretyship bonds originated hundreds of years ago as a mechanism through which trade over long distance could be encouraged. They are frequently used in the construction industry: in order to obtain a contract to build the project, the general contractor (and often the sub-contractors as well) must provide the owner a bond for its performance of the terms of the contract. Conversely, owners and contractors may also provide payment bonds to ensure that subcontractors and supppliers are paid for work done. Under the Miller Act, payment and performance bonds are required for general contractors on all U.S. federal government construction projects where the contract price exceeds $100,000.00.
Surety bonds are also used in other situations, for example, to secure the proper performance of fiduciary duties by persons in positions of private or public trust.
A key term in nearly every surety bond is the penal sum. This is a specified amount of money which is the maximum amount that the surety will be required to pay in the event of the principal's default. This allows the surety to assess the risk involved in giving the bond; the premium charged is determined accordingly.
If the principal defaults and the surety turns out to be insolvent, the purpose of the bond is rendered nugatory. Thus, the surety on a bond is usually an insurance company whose solvency is verified by private audit, governmental regulation, or both.
A bail bond is a type of surety bond used to secure the release from custody of a person charged with a criminal offense. Under such a contract, the principal is the accused, the obligee is the government, and the surety is the bail bondsman.
In 2001, a new type of suretyship bond called a Sure-T bond was announced. Protecting Internet auction (e.g., eBay) users in the case of default by a bidder or seller, the Sure-T bond further extends the reach of suretyship bonds in encouraging long-distance trade.