There are two instances when money is involved when it comes to posting a bail bond. The first is a cash bond. The full amount of the bond is paid in cash to the jail for a defendant to get released. The cash is then transferred to the county clerk, where they hold onto it until the case is over, and it is given back to the defendant as long as they went to every single court date.
When someone contracts through a bail bondsman to get released, they pay the bail bondsman a percentage of the fee. That is the other time a monetary transaction happens. The bail bondsman then guarantees in writing that the defendant will show up to all of their court dates and promises to pay the full amount of the bond if they do not. The bail bondsman never gives any actual money to the court. They act as the insurance company for the defendant.