Answered by Shaykh Faraz Rabbani
Does one have to make up witr prayer?
Walaikum assalam wa rahmatullah,
In the Hanafi school, the witr prayer is necessary (wajib), and thus necessary to make up with other missed prayers.
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Imam Kasani (Allah have mercy on him),
“If one does not perform Witr in its time… it is necessary to make it up according to our scholars because it is a necessary (wajib) prayer, so it is compensated by making it up, just like obligatory prayers.” [Kasani, Bada’i` al-Sana’i`, 1.272]