How quickly the landlord must respond
A California landlord must address a rat or mouse infestation within a reasonable time after being notified. There is no fixed deadline in the law, but the worse the infestation and the health risk, the faster the landlord is expected to act.
For a serious infestation, "reasonable" usually means arranging professional treatment and sealing entry points promptly — not letting weeks pass with no real response. Rodents breed quickly, so delay makes the problem worse and prolongs the health risks that come from droppings, urine, and contaminated food.
Reporting the problem in writing and keeping copies helps establish exactly when the landlord's clock started. Note each report and each follow-up. If your landlord lets a rodent infestation drag on well past a reasonable time, you may have several options, and a free review can help you decide what to do next.
This is general information about California tenant rights, not legal advice. Every situation is different.