Answered by Shaykh Faraz Rabbani
Question: I would like to ask about neutering cats, as pets, they can make house najis so some poeple solve it with neutering them, but would this be ok, as it means we rid them of something Allah created them with.
Answer: Walaikum assalam,
In the Hanafi school, it would be permitted to do so if there is a clear benefit in doing so.
It is mentioned in the Fatawa al-Hindiyya, one of the most definitive works in Hanafi fiqh and used as an authority by Hanafi scholars everywhere,
“If there is a [clear] benefit or aversion of harm in castrating a cat, there is nothing wrong with it, as mentioned in al-Kubra.” [5.357]
This is also confirmed by Imam Haskafi in Durr al-Mukhtar.