Wa alaykum salam wa rahmatuLlahi wa barakatuHu,

Imam Nawawi stated that it is recommended [mustahabb] for one to write صلى الله عليه وسلم out in full after mention of the Prophet Muhammad. (Sharh Sahih Muslim v. 1, p. 38) According to some, like Hafiz Sakhawi, using an acronym in place of writing it in full is better to avoid [khilaf al-awla]; and according to others, like Hafiz ‘Iraqi, it is disliked [makruh]. (Fath al-Mughith v. 3, p. 47)

It should also be noted that the acronyms, like “SAW” and “SAWS,” are commonly used by Muslims for “SallAllah alayhie wa sallam.” Yet, they may be used for other phrases too. Thus, when featured after the Prophet Muhammad’s name, we understand what they mean. Even so, writing it out in full removes all ambiguity.

Therefore, it is advisable that one write it in full.

May Allah forgive us and guide us. May He send the choicest of prayers and salutations on RasulAllah.

And Allah knows best.

Shafiifiqh.com Fatwa Dept.