Reference: Sharh ‘Umdatil-Fiqh – Tape No.7, Question No.43
Question: If someone wants to do wudhoo in the toilet – in the [same] place where he relieves himself, is it permissible for him to utter “bismillaah” [بسم الله] before doing wudhoo?
Response: Yes; Shaykh Ibn Baaz رحمه الله issued a fatwa that he must say “bismillaah”. That is because uttering “bismillaah” [before wudhoo] is obligatory, so he must utter “bismillaah” even if he is in the toilet; he must fulfill that which is required of him.
