Intended four rak‘as but forgetfully gave the salam after three: what is the ruling on this prayer?

Question

Zayd made the niyya (intention) for four rak‘as of fard, forgetfully sat in the third rak‘a and, having recited al-tahiyyat and the blessed salawat, gave the salam. After the prayer he remembered that he had prayed three rak‘as. The question is: what becomes of the said prayer? Has it become batil (void)?

Answer

The fard status (fardiyya) of this prayer has become void (batil); it is possible that in the Hereafter he will receive the reward of two rak‘as.

Source: Fatawa Mahmudiyya

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