Sajda al-Sahw Was Missed out of Forgetfulness

Question

If sajda al-sahw is missed out of forgetfulness and this becomes known a little while later, is it necessary to repeat the prayer or not? If repeating (i'ada) is necessary, is it in all prayers or specifically in the zuhr and 'isha' prayers?

Answer

If the sajda [al-sahw] is missed out of forgetfulness and [the worshipper] has not done anything contrary to the prayer, and then remembers, he should perform sajda al-sahw and complete the prayer; otherwise he should pray it again, whatever prayer it may be.

Source: Fatawa Mahmudiyya

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