You might not be allowed to register your pet without desexing your pet. Other councils will charge you more to register an undesexed pet. If you don't desex your pet in a state where it's a legal requirement, you face being hit with a big fine.
Owners of undesexed pets can be hit with high vet bills if their animal gets injured while out roaming or has complications during pregnancy and birth
If you plan to go on holiday, many kennels and catteries refuse to take undesexed dogs and cats, while others charge more to do so. And local councils charge more – over four times as much – to register an undesexed animal.