Fatawa from Permanent Committee
Q3: Is it permissible for a person to perform `Umrah before the obligatory Hajj?
A: Yes, it is permissible for a person to perform `Umrah before Hajj because the Prophet (peace be upon him) and his Companions performed `Umrah before the obligatory Hajj.
May Allah grant us success! May peace and blessings be upon our Prophet Muhammad, his family, and Companions!
Permanent Committee for Scholarly Research and Ifta’
Source:http://www.alifta.com/
Q 11: What is the ruling on a person who performs `Umrah (lesser pilgrimage) before Hajj, although the former is only an act of Sunnah?
A: The correct view of the two rulings of the scholars is that `Umrah is obligatory, because Allah states:Surah Al-Baqarah, 2: 196
And perform properly (i.e. all the ceremonies according to the ways of Prophet Muhammad peace be upon him) the Hajj and ‘Umrah (i.e. the pilgrimage to Makkah) for Allâh. 
There are also other Hadiths narrated in this regard. If a Muslim performs `Umrah before Hajj during the months of Hajj and performs Hajj in the same year, then he has performed Tamattu` Hajj (combining Hajj and `Umrah with a break in between) which is better than the Ifrad Hajj (performing Hajj only) and Qiran Hajj (combining Hajj and `Umrah simultaneously) for the one who has not brought a hadiy with him. It is reported that the Prophet (peace be upon him) told the Sahabah (Companions of the Prophet) who did not bring sacrificial animals:
Make it `Umrah, for if I had formerly known what I came to know lately, I would not have driven the Hadiy with me and would have finished the state of Ihram along with the people when they finished it. 
May Allah grant us success! May peace and blessings be upon our Prophet Muhammad, his family, and Companions!
Permanent Committee for Scholarly Research and Ifta’
Source: http://www.alifta.com/
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