Doing ghusl on Fridays is mustahabb, not obligatory, according to the majority of fuqaha’, although some of them were of the view that it is obligatory.
This ghusl is prescribed for those who come to Jumu‘ah prayers, whether men or women, although it is men who are addressed in the verse which tells them to attend the prayer, as Allaah says (interpretation of the meaning):
“O you who believe (Muslims)! When the call is proclaimed for the Salaah (prayer) on Friday (Jumu‘ah prayer), come to the remembrance of Allaah [Jumu‘ah religious talk (Khutbah) and Salaah (prayer)] and leave off business (and every other thing). That is better for you if you did but know!”
But if a woman attends Jumu‘ah prayer, it is prescribed for her to do ghusl for it and observe its etiquette.
Ibn Hibbaan wrote a chapter in his Saheeh entitled: It is mustahabb for women to do ghusl for Jumu‘ah if they want to attend it. Then he quoted the hadeeth of ‘Uthmaan ibn Waaqid al-‘Umari from Naafi‘ from Ibn ‘Umar, who said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “Whoever comes to Jumu‘ah, man or woman, let him do ghusl.”
The authenticity of the hadeeth is agreed upon, apart from the additional words “man or woman”. This additional material was narrated by Ibn Khuzaymah, Ibn Hibbaan, and al-Bayhaqi in al-Sunan, and that there was a difference of opinion as to whether it is saheeh or not.
It was classed as saheeh by al-Nawawi (may Allah have mercy on him) in al-Majmoo‘ (4/405) and Ibn Mulaqqin in al-Badr al-Muneer (4/649).
Al-Haafiz Ibn Hajar (may Allah have mercy on him) said in al-Fath (2/358): According to the report of ‘Uthmaan ibn Waaqid from Naafi‘, which is narrated by Abu ‘Awaanah, Ibn Khuzaymah and Ibn Hibbaan in their Saheehs with the wording, “Whoever comes to Jumu‘ah, man or woman, let him do ghusl, and whoever does not come to it does not have to do ghusl,” its men are thiqaat (trustworthy). But al-Bazzaar said: I am afraid that there is some wahm (weakness of memory) in ‘Uthmaan ibn ‘Aaqid.
What al-Bazzaar was afraid of, namely wahm (weak memory) of ‘Uthmaan ibn Waaqid, was stated with certainty by Abu Dawood, the author of al-Sunan, may Allah have mercy on him.
Abu ‘Ubayd al-Aajurri said: I asked Abu Dawood about him and he said: He is da‘eef (weak). I said to Abu Dawood: ‘Abbaas ibn Muhammad narrated from Yahya ibn Ma‘een that he is trustworthy. He said: He is da‘eef (weak). He narrated that the Prophet (blessings and peace of Allah be upon him) said: “Whoever comes to Jumu‘ah, man or woman, let him do ghusl.”, but we do not know of anyone who says this apart from him.
End quote from Tahdheeb al-Kamaal, 19/505
Al-Albaani (may Allah have mercy on him) stated definitively that this additional material is odd and he classed it as weak, as it says in al-Silsilah al-Da‘eefah (8/430).
What may support the view that women should do ghusl for Jumu‘ah is the reports narrated by Ibn Abi Shaybah in his Musannaf from ‘Ubaydah bint Naa’il who said: I heard Ibn ‘Umar and the daughter of Sa‘d ibn Abi Waqqaas say: Whoever among you (women) comes to Jumu‘ah, let her do ghusl. Something similar was narrated from Tawoos, and it was narrated from Shaqeeq that he used to tell his family, both men and women, to do ghusl on Fridays. See al-Musannaf (2/9).
Doing ghusl for Jumu‘ah makes sense, because it is cleanliness and puts a stop to unpleasant odours that annoy other people present. Hence women are asked to do that if they want to attend.
Al-Haafiz said in al-Fath: al-Zayn ibn al-Muneer said: And it was narrated from Maalik that whoever attends Jumu‘ah apart from men, if their attendance is to seek virtue, it is prescribed for them to do ghusl and observe all the etiquettes of Jumu‘ah, but if they attend on the spur of the moment, then no.
End quote from al-Fath al-Baari.
Al-Nawawi (may Allah have mercy on him) said in al-Majmoo‘ (4/405):
Doing ghusl on Friday is Sunnah, not obligatory in the sense that not doing it is a sin, and there is no difference of opinion among us concerning that. With regard to the one for whom it is Sunnah, there are four views, but the correct view that is supported by the text and regard by the author and the majority as the correct view is the following: It is Sunnah for everyone who wants to attend Jumu‘ah, man, woman, child, traveller, slave and others, because of the apparent meaning of the hadeeth of Ibn ‘Umar, and because the aim is cleanliness, and they are all the same with regard to that. It is not Sunnah for the one who does not intend to attend, even if he is one of those who should attend Jumu‘ah, because of the meaning of the hadeeth and because the reason is no longer present; and because of the hadeeth of Ibn ‘Umar, according to which the Prophet (blessings and peace of Allah be upon him) said: “Whoever comes to Jumu‘ah, man or woman, let him do ghusl, and whoever does not come to it, man or woman, does not have to do ghusl.” Narrated by al-Bayhaqi with this wording and with a saheeh isnaad. End quote.
And Allah knows best.