Umrah is an act of worship which is performed usually either as Mufradah or Umrah of Tamattu'. These are names of two different pilgrimages performed on different occasions. It has been said by religious authorities and grand jurisprudents that it is recommended to repeat an umrah pilgrimage as it is permissible. However, they have discrepant views about the time gap between two umrah pilgrimages of which one he might perform principally on his behalf and the other on behalf of a relative. Some scholars have allowed repeating umrah without restricting or confining it within a special time span. Hence, according to them it is permissible to repeat umrah without there being any time span between the two pilgrimages.[1]  However, some other scholars are of the view that in every lunar month only one umrah may be performed, though that umrah could be performed at the end of the month of Rajab and the other at the beginning of Sha'ban.[2]
As for the time gap between Umrah of Tamattu' and Umrah Mufradah, it must be noted that a number of jurisprudents do not consider any time gap to be necessary between the two umrah pilgrimages and it does not make an difference whether the two umrah pilgrimages are done before the obligatory hajj or after it.[3] Some others, as was mentioned above, allows only one umrah (Umrah of Tamattu' or Umrah Mufradah) in every lunar month.[4] Hence, if a pilgrim performs Umrah of Tamattu' in one month, he cannot perform Umrah Mufradah in the same month.
Note:
When performing two umrah pilgrimages, it is necessary that Umrah Mufradah should precede Umrah of Tamattu and if he wants to perform it after Umrah of Tamattu', he should make sure to perform it after performing the obligatory hajj (Hajj al-Tamattu'). Because based on the verdicts of grand religious authorities, one should not create a gap between Umrah of Tamattu' and Hajj al-Tamattu' by performing Umrah Mufradah in between them.[5] If he performs it, the validity of Umrah Mufrada would be a matter of objection (ishkaal);[6] but Umrah of Tamattu' and Hajj al-Tamattu' will remain in order.[7]

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