Collateral is something of value used to secure a bail bond. This can be in the form of cash, credit card, signatures, real property, automobiles, stocks, and other things of value. If cash collateral is given, it is held in a separate trust account either managed by the bonding agency or the surety company the agent writes for. If you used a credit card, a percentage fee may be charge on any collateral returned.
The most common form of collateral is the use of an indemnity agreement and promissory note. These two contacts hold the signers financially responsible for the full amount of the bond on the event of forfeiture. This is the simplest and lowest from of collateral and is used mainly on smaller bonds.