How to Say the Closing Salam in Prayer

From Abdulaziz ibn Abdullah ibn Baz to the honorable brother A. A. A. K., may Allah guide him to what is right. Peace be upon you, and Allah’s mercy and blessings. After that: With reference to your inquiry, registered with the Research Department under number 1221 on 23/4/1405 AH, we inform you that it has been reviewed, and here is the answer to each question, followed by its explanation:

Q: Is it permissible for the imam, when saying the salam in prayer, to say “Peace be upon you, and Allah’s mercy and blessings,” or should he suffice with saying “Peace be upon you, and Allah’s mercy”? And if he adds the phrase “and blessings” to the salam, is the prayer invalid or valid?

A: It is better to restrict oneself to saying “Peace be upon you, and Allah’s mercy,” because this is what is preserved from the Prophet (peace and blessings be upon him). As for adding “and blessings,” there is disagreement among the scholars regarding its authenticity, and it is better to leave it out. However, if one does say it, the prayer is not invalidated by it.
And success is from Allah, and may Allah send prayers and blessings upon our Prophet Muhammad, his family, and his Companions.