Written by
Ramiro Quezada Jr.
Published on
October 24, 2026

When you co-sign a bail bond, you are promising the bail company that the defendant will go to every court date, and that you will cover the costs if they don't. That can include the premium, any payment plan balance and, if the defendant skips court and the bond is forfeited, money up to the full bail amount. It's a serious financial commitment, so it helps to know exactly what you're signing.
A co-signer, also called an indemnitor, is the person who signs the bail paperwork alongside the defendant and takes financial responsibility for the bond. Usually this is a parent, spouse, partner, relative or close friend.
The bail agent posts a bond with the court that guarantees the full bail amount. In return, the co-signer signs an indemnity agreement. That agreement says the co-signer will repay the bail company for losses and costs if the defendant doesn't hold up their end. The exact terms are in the contract you sign, so read it before you put your name on it.
Your main job is helping make sure the defendant shows up to every court date until the case is over or the bond is exonerated (released). That means knowing the dates, reminding them, and telling the bail agent right away if anything changes, like a new address, a new phone number or a missed check-in.
The premium is the fee for posting the bond. In California, premiums are typically 10% of the bail amount, based on rates filed with the California Department of Insurance. Payment plans are available. If you sign as the person responsible for the premium or a payment plan, you're on the hook for those payments even if the defendant's case goes well.
This is the part people most often miss. If the defendant fails to appear and the court ultimately enters a judgment on the bond, the judgment is for the bond amount plus costs. Under the indemnity agreement, the bail company can then look to the co-signer to repay that loss, along with costs the contract allows. If you co-sign a $50,000 bond, you should be prepared for the possibility of owing up to $50,000.
Collateral is property that secures the bond, such as cash, a vehicle title or a lien on real estate. Not every bond requires collateral. It depends on the bail amount, the case and the people signing.
California regulations give you some protections:
California's bail forfeiture process is set out in Penal Code section 1305. Here is how it generally works.
For a co-signer, the takeaway is simple: the faster the defendant gets back to court, the better your position. If a court date is missed, call the bail agent immediately. Encouraging the defendant to return voluntarily is almost always the best path.
Sometimes. If you lose confidence that the defendant will go to court, talk to the bail agent right away. California law (Penal Code 1300) allows the bail company to surrender the defendant to custody before any forfeiture, and the court can then exonerate the bail. That ends the bond, and with it, your future exposure on that bond.
There are trade-offs. Surrender means the defendant goes back into custody. The premium is the fee for the bond and generally isn't refunded; under Penal Code 1300, a court may order it returned in whole or in part only in limited situations, such as when it finds there was no good cause for the surrender. Ask what your options are before you decide.
Your responsibility usually ends when the bond is exonerated, which typically happens when the case is resolved or the defendant is otherwise released from the bond's obligation. Ask the agent to confirm in writing when that happens, and to return any collateral.
This article is general information, not legal advice. For questions about your case, talk to a criminal defense attorney.
If you're still learning the basics, our guide on how bail works in California walks through the full process from arrest to release.
OnCall's licensed bail agents answer 24/7, in English and Spanish, and we'll walk you through exactly what you're signing before you sign it. You can complete the paperwork from your phone. Call (951) 339-3801, send us a message, or start bail online.