The Bank Guarantee Slip is a financial operation in which a bank issues a document (the bank guarantee slip) in order to guarantee certain obligations that any person, called a client "Client (economy)"), contracts in favor of a third party.

The obligation guaranteed by the bank is that of its client towards a third party and the surety operates by empowering the beneficiary of the bank note to demand payment from the bank at his sole request, when the holder of the note does not comply with the assumed obligation.

For this system to operate, article 69 no. 13 of the General Banking Law (former Article 86 no. 10 of Decree with force of law 252), in the Republic of Chile, declares funds unseizable by third parties foreign to the contract or obligation they guarantee.

In turn, two legal relationships coexist in parallel:

This second legal relationship does not matter to the bank and is not governed by the rules of the Bank Guarantee Note, but by the common rules of the obligations that the policyholder is guaranteeing.

The only obligation that the bank has with the beneficiary is if he receives payment.