Is My Salah Valid if I Missed an Obligatory Part Out of Ignorance?

Walekumussalam,

The principle of Salah is that if any obligatory part (pillar) of the prayer is missed, the prayer is not valid—whether it was missed intentionally, by forgetfulness, or out of ignorance. Therefore, such a prayer is not considered fulfilled and it becomes necessary to make it up (qada).

This is mentioned in reliable books of Islamic jurisprudence such as Al-Hidayah, Bada'i al-Sana'i, and Radd al-Mukhtar, where it is stated that leaving a pillar invalidates the prayer.

Therefore, if someone missed an obligatory pillar of the prayer even out of ignorance, the prayer will not be valid and it is necessary to perform its qada.