On which hand should the wedding ring be worn
In the name of Allah, the most Beneficent, the most Merciful.
Firstly, it should be understood that there is no evidence in Islam which permits the wearing of a wedding or engagement ring. It is better, both for males and females, to avoid wearing the ring on the occasion of marriage, in particular if it is done with the intention to imitate immoral people.
However, if the ring is being worn because it was gift from the husband etc… then it will be permissible for women to wear the ring on whichever finger they want. As for men then if it is a silver ring where the silver is equal to 4.86 grams then it is Makruh Tanzihi to wear it on the middle and index finger. The reason being is that these fingers are more frequently used; hence it will be preferable to wear it on the ring finger or on the small finger. (Takmila Fath Al-Mulhim p.139 v.4 & Ahsanul Fatawa p.69 v.8)
Furthermore, it is narrated by Saaidina Ali (RA) that the Prophet of Allah (SAW) forbade him from wearing a ring on this finger and this finger. The narrator says he pointed to the middle and index finger. (Sahih Muslim p.197 v.2)
Regarding which hand you should wear the ring then there are two types of narrations. Most of the narrations indicate that the Prophet of Allah Sallallahu Alahi Wasalam wore his ring on his right hand whilst others indicate that he wore it on his left hand. It is possible that the Prophet of Allah Sallallahu Alahi Wasalam initially wore his ring on the right hand and thereafter resorted to wearing it on his left hand. It could also be so that the Prophet of Allah Sallallahu Alahi Wasalam occasionally wore his ring on his left hand due to a need, or to show its permissibility. (Takmilah Fathul Mulhim p.82 v.4)
The upshot of it is that it is permissible to wear the ring on whichever hand one wishes.
Only Allah Knows Best.
Mohammed Tosir Miah
Darul Ifta Birmingham.