It is the one record every pet needs, and the one most often out of date.
What it must show
The certificate lists your pet's name, species, breed and age, the vaccine product, the date given, the duration and the signing veterinarian. The expiry date matters most. For boarding, the certificate must remain valid through the last day of the stay. If it expires during a trip, get the booster before you go.
California law
Health and Safety Code section 121690 requires dog owners to have dogs three months or older vaccinated against rabies by a licensed veterinarian with an approved vaccine, unless a vet documents a medical exemption. Counties also use the certificate to license a dog; Solano and Yolo require a valid certificate for a license, and a license expires early on the rabies expiry date.
The three-year point
The kennel's vaccination page says rabies is given every three years in healthy adult dogs and cats. Your vet sets the actual schedule. A first rabies vaccine is usually followed by a booster a year later, and then the longer interval. Ask your vet to print the certificate with the expiry date in full.
Sending it in
Upload the certificate to your online account, email it or bring a copy to the first check-in. See rabies vaccine for dogs, rabies vaccine for cats and rabies exemptions in California.
If your pet is overdue
A pet whose rabies vaccine has lapsed needs a booster before boarding. Call your vet; many clinics can see you the same week. A pet that has never had rabies vaccine needs the first dose and, for a certificate, a vet visit. Do this at least a few days before the stay. If your vet has granted a medical exemption for a dog, ask the kennel about its policy before booking, because the vaccination page says no pet is accepted without proof of a current rabies vaccine.
Keep a photo of the certificate on your phone. It is also useful for dog licensing, travel and any lost-pet situation.