Sayyiduna Abu Sa'id Khudri (may Allah be pleased with him) narrates: The Noble Prophet (peace and blessings be upon him) said: "When a person becomes doubtful during prayer and does not know how many rak'ahs he has performed, three or four, then he should put aside the doubt and base it on what he is certain of. Then, before saying the salam, he should perform two prostrations of forgetfulness (sajda sahw). If he has performed five rak'ahs, then the even number among them will be his prayer, and if he has performed four rak'ahs, then these two (prostrations) will be a means of humiliation for Satan."

Sayyiduna Abu Sa'id Khudri (may Allah be pleased with him) narrates: The Noble Prophet (peace and blessings be upon him) said: "When a person has doubt about his prayer, he should put aside the doubt and base (his action) on what is certain, and when he has certainly completed the prayer (then at the end) he should perform two prostrations of forgetfulness. If his prayer was complete, then the extra rak‘ah and two prostrations will be counted as voluntary for him, and if his prayer was incomplete before, then through that one rak‘ah his prayer will be completed, and both prostrations of forgetfulness will rub the nose of Satan in the dust."

Sayyiduna Abu Sa'id Khudri (may Allah be pleased with him) narrates this statement of the Noble Prophet (peace and blessings be upon him): "When a person has doubt about his prayer and does not know how many rak'ahs he has performed: four or three? Then he should put aside the doubt and base it on what is certain, then stand up and recite (Qira'at) and perform one rak'ah. Then when he is sitting (i.e., reciting Tashahhud), before saying the salam, he should perform two prostrations of forgetfulness (sajda sahw). If he had already performed four rak'ahs, then now one rak'ah will be extra for him, and these two prostrations will make it even, which was the fifth rak'ah. And if he had already performed three rak'ahs, then the fourth rak'ah will complete it for him, and the two prostrations of forgetfulness will rub the nose of Satan in the dust."

Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates: The Noble Prophet (peace and blessings be upon him) said: "When a person has doubt about his prayer, if he is certain that he has performed three rak‘ahs, then he should perform one more rak‘ah and do two prostrations (of forgetfulness), then sit for tashahhud, and when he has finished and nothing remains to be recited except the salam, at that time he should perform two prostrations of forgetfulness, then he should say the salam. If he had performed three rak‘ahs, then the rak‘ah he has now performed will be the fourth, and the two prostrations of forgetfulness will rub the nose of Satan in the dust. And if he had already performed four rak‘ahs, then the one he has now performed will be the fifth, and these two prostrations will make this fifth rak‘ah even."

Abdul Muhaymin narrates from his father, who narrates from his grandfather, Sayyiduna Mundhir bin Amr (may Allah be pleased with him), that he said: This companion was among the leaders (nuqaba) of Banu Sa'idah. He narrates: The Noble Prophet (peace and blessings be upon him) performed two prostrations of forgetfulness (sajda sahw) before saying the salam. According to one statement, this is the only narration transmitted from Sayyiduna Mundhir bin Amr (may Allah be pleased with him).

Sayyiduna Abu Hurairah (may Allah be pleased with him) narrates: The Noble Prophet (peace and blessings be upon him) said to us: "When a person is performing prayer and he is unsure whether he has performed more or fewer rak‘ahs, then he should perform two prostrations of forgetfulness while he is sitting (i.e., during the tashahhud), and then after that he should say the salam."