How much does it cost to sterilise my pet? Pet sterilisation costs vary depending on a number of factors including the type of animal, its age, size and gender. Expand The cost to sterilise or de-sex your pet will vary on a number of factors including: the type of animal (e.g. dog or cat or rabbit) the age of the animal the animal's size the animal's gender whether your pet has any underlying medical conditions Under the RSPCA's Pet Sterilisation Program, you will be required to pay 25% of the cost directly to the vet at the time of the procedure. This includes the cost of de-sexing and microchipping your cat or dog. It does not include any additional costs that may be charged, or pre- or post-operative medications or preparations. You must use one of the vets who have signed up to offer their services. When your application is approved, you will receive a unique voucher number which you must give to the vet at the time you make your booking. RSPCA, through the WA Government grant, will cover 75% of the cost of sterilising your pet.