There are different schools of thought regarding the cutting of hair before making the Qurbani sacrifice.
In the Hanbali madhab (school of thought), it is considered haraam (forbidden) to cut your hair if you’re donating Qurbani (sacrifice).
According to the majority of the scholars, however, to refrain from cutting your hair is recommended. It is best to seek advice according to your madhab (school of thought).
See more Qurbani rules here.
There are different schools of thought regarding the cutting of nails before making the Qurbani sacrifice.
If your madhab (school of thought) offers the prohibition of cutting hair and nails before making the Qurbani, the prohibition starts from the 1st of Dhul Hijjah and lasts until one has made the Qurbani (sacrifice) and can resume cutting hair and nails thereafter.
In a famous hadith, Prophet Muhammad (peace be upon him) says:

“When the ten days (of Dhu’l-Hijjah) begin – and any one of you wants to offer a sacrifice, let him refrain (from cutting) his hair and nails.”
(Muslim)
A number of scholars used this hadith as the basis for his statement that refraining from cutting your hair and nails forms part of the completion of the sacrificial rite of the Qurbani (sacrifice).
Find out more information on Qurbani rules and where to make your Qurbani donation.
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