Pillars & FiqhThe udhiyah is a confirmed sunnah (sunnah mu'akkadah) for one who is able to afford it, according to the majority of scholars, and it is not obligatory — this is what Shaykh Ibn Baz preferred, citing as evidence the Prophet's ﷺ continual practice of sacrificing every year. Abu Hanifah held that it is obligatory upon the resident who has sufficient means. So whoever leaves it while being able to afford it has missed out on a great good, but there is no sin upon him.
Source:فتوى ابن باز [خلاف: الجمهور سنة مؤكدة، وأبو حنيفة على وجوبها]