Ruling 1185

In nine situations, if one has a doubt about the number of rakʿahs in a four rakʿah prayer, he must think [about the doubt]; then, if he becomes certain or he supposes that a particular possibility is correct, he must act according to that possibility and complete the prayer; otherwise, he must act according to the instructions that will be mentioned later. The nine situations are set out below.

First: after starting the second sajdah, one doubts whether he has performed two rakʿahs or three rakʿahs. In this situation, he must assume he has performed three rakʿahs and perform one more rakʿah and complete the prayer, and after the prayer, he must perform one rakʿah of ṣalāt al-iḥtiyāṭ in a standing position. Based on obligatory precaution performing two rakʿahs in a sitting position will not suffice.
Second: after starting the second sajdah, one doubts whether he has performed two rakʿahs or four rakʿahs. In this situation, he must assume he has performed four rakʿahs and complete the prayer; and after the prayer, he must perform two rakʿahs of ṣalāt al‐iḥtiyāṭ in a standing position.
Third: after starting the second sajdah, one doubts whether he has performed two, three, or four rakʿahs. In this situation, he must assume he has performed four rakʿahs and after the prayer he must perform two rakʿahs of ṣalāt al‐iḥtiyāṭ in a standing position followed by two rakʿahs in a sitting position.
Fourth: after starting the second sajdah, one doubts whether he has performed four or five rakʿahs. In this situation, he must assume he has performed four rakʿahs, complete the prayer, and after the prayer, he must perform sajdatā al‐sahw. Similarly, whenever the weaker possibility of a doubt is four rakʿahs – for example, he doubts whether he has performed four or six rakʿahs – and whenever one doubts whether he has performed four rakʿahs or more or less after having started the second sajdah, he can assume he has performed four rakʿahs and he must act in accordance with the instructions applicable to both possibilities of his doubt; i.e. he must perform ṣalāt al‐iḥtiyāṭ based on the possibility that he had performed less than four rakʿahs, and he must then perform sajdatā al‐sahw based on the possibility that he had performed more than four rakʿahs.
In each case, if any of these four doubts arise after the first sajdah and before performing the second sajdah, his prayer is invalid.
Fifth: at any stage of the prayer, one doubts whether he has performed three or four rakʿahs. In this situation, he must assume he has performed four rakʿahs and complete the prayer, after the prayer he must perform one rakʿah of ṣalāt al‐iḥtiyāṭ in a standing position or two rakʿahs in a sitting position.
Sixth: while standing, one doubts whether he has performed four or five rakʿahs. In this situation, he must sit down, say tashahhud and the salām of the prayer, and perform one rakʿah of ṣalāt al‐iḥtiyāṭ in a standing position or two rakʿahs in a sitting position.
Seventh: while standing, one doubts whether he has performed three or five rakʿahs. In this situation, he must sit down, say tashahhud and the salām of the prayer, and perform two rakʿahs of ṣalāt al-iḥtiyāṭ in a standing position.
Eighth: while standing, one doubts whether he has performed three, four, or five rakʿahs. In this situation, he must sit down, say tashahhud and the salām of the prayer, perform two rakʿahs of ṣalāt al‐iḥtiyāṭ in a standing position, and then perform two rakʿahs in a sitting position.
Ninth: while standing, one doubts whether he has performed five or six rakʿahs. In this situation, he must sit down, say tashahhud and the salām of the prayer, and then perform sajdatā al‐sahw.