Shaikh Ibn ul-‘Uthaymeen rahimahullah said:
“On some doors there are bells that are used to seek permission. This, also, does not enter into the prohibition because it is not connected to an animal or what resembles that nor does it make the melody which is prohibited by the Messenger (ﷺ) “. [Sharh Riyad as-Saliheen (6/432)]
Shaikh al-Albani rahimahullah:
“I say: different types of bells have been invented in this era for different beneficial purposes like the bell in the alarm clock to awake the one sleeping, or the ringing of the telephone, or the bell used in the governmental departments ,or the houses, and like that. So do these enter into the Ahaadith mentioned and what has its meaning? My answer: No because that does not resemble the Naqoos (the bell used by the Christians) not in sound nor in form. And Allah Knows best“.
[Jilbab Mar’atul-Muslimah pg. 169]
The Permanent Committee was asked:
Question: What is the bell that is prohibited ? Knowing that there are electronic bells that produce sounds of birds and clock bells wherein a piece of iron hits another [inside] and other than that of the types?
Answer: “Bells used in the houses and schools and the likes are allowed as long as they do not include prohibited things like resembling the Naqoos of the Christians or it has a musical sound. Then (in that case) it would be prohibited due to that. And with Allah is Divine Success. And May Peace and Blessings be upon our Prophet Muhammad, his Family, and Companions”.
[Fatwa no. 18952]
Shaikh Bakr Abu Zaid rahimahullah said:
“And similar to it in our time is the electronic doorbells which are on the houses. They should be used with gentleness and not with force nor held for a long duration“.
[Adaab ul-Haatif pg. 11]
And Allah Knows Best
Faisal Ibn Abdul Qaadir Ibn Hassan