1 The price for cat euthanasia differs from one area to another and by the size of the cat. 2  However, the average cost among veterinarians ranges from $45 to $150. The additional fee will make the total cost to range from $140 to $300. 2  After euthanasia, the burial of the cat will cost more. 3  This will either lead you to cremation or a cemetery burial. 4  This is an optional choice for pet owners.