If you don't know your pet's microchip number, you can contact your nearest Vet or find your closest Greencross Vet or council or animal welfare shelter to scan your pet and supply you with the microchip number which you can then add to your Pet's PetCloud Profile and store it there for safe keeping.
Currently there are 6 private microchip registries and 1 NSW State government registry:
Cats and dogs must be microchipped when:
1. Sold (seller responsibility)
2. Given away (responsibility on the person giving away the animal)
3. Before reaching the age of 12 weeks