I lost the chargeback dispute with the bank. Can I still sue the guest for the room?

Losing a card dispute feels final because it is presented as a decision, but a chargeback is not an adjudication of anything. When a cardholder disputes a transaction, their issuing bank applies the card brand's operating rules, weighs whatever documents the two banks exchanged, and moves the funds. Those rules are a private commercial arrangement among networks, issuers, acquirers and merchants. They were never designed to determine legal liability, and a California judge has no obligation to defer to the outcome. The guest's duty to pay for the nights they occupied arises somewhere else entirely: in the agreement they entered when they took the room, and in the plain fact that they received lodging.

That separation is what makes this segment work at all. The bank asked one question, which was whether the transaction should stand under network rules. The court asks a different one, which is whether this person owes this money. You can lose the first and win the second on the same facts, and the reverse is also true. What changes between the two forums is the evidence that matters. The issuer looked at documents your acquirer forwarded within a compressed deadline. The court will look at whatever you bring, including testimony from the staff who checked the guest in, which no chargeback process ever considers.