It is claimed that it is haraam for women to adopt the surname of their husbands.

Answer

There is no basis for claiming that it is not permissible for a woman to adopt the surname of her husband. Those who make this claim should provide daleel (proof). There is nothing in the Shariah to negate this permissibility. The adoption of the husband's surname is for convenience and to avoid confusion. The claimants cite the Qur'aanic aayat in which Allah Ta'ala negates Zaid (radhiyallahu anhu) being the son of Rasulullah (sallallahu alayhi wasallam). But this aayat is never a basis for the claim of the Salafis. The two issues are vastly different.

Changing the surname is tantamount to saying: 'I am the wife of Mr. Patel". There is nothing wrong – nothing in conflict with the Shariah for a wife to say: 'I am the wife of Abdullah or Patel or Ahmed.' Now instead of writing every time after her name: Faatimah, the Wife of Ebrahim Cassim', the wife says in an abbreviated form: Faatimah Cassim/Patel/Ahmed. Everyone knows from this abbreviation that she is saying: 'I am Faatimah who is the wife of Ebrahim Cassim.'

There is nothing logically nor Islamically wrong with this statement and its abbreviation.