What is the ruling regarding someone who assumed ihram (ritual consecration) for ‘Umrah but could not complete its rituals due to severe crowdedness or old age?

All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and messenger.

Whoever has assumed Ihraam for ‘Umrah but could not complete its rituals should maintain his Ihraam until he is able to do. It is impermissible for him to revoke his ‘Umrah. Allaah Almighty says (what means): {And complete the Hajj and ‘Umrah for Allah….} [Quran 2: 196]

In case he returns to his country without completing the Tawaaf (circumambulation) of ‘Umrah although having been able to do so by waiting for a time when there was less crowdedness, then he should remain in a state of Ihraam until he is able to come back to Makkah and complete the ‘Umrah. In case he gets sick or becomes permanently unable to complete the rituals and did not initially make a condition at the time of assuming Ihraam by saying "I intend to perform 'Umrah, but if something hinders me from completing it, then I will end my Ihraam once I am hindered," as the questioner mentioned, then in this case, he may end his Ihraam, offer a Hady (Hajj sacrificial animal) and shave his head. He is then treated like one who was prevented by an enemy to complete the rituals. This is based on the general indication of the verse where Allaah Almighty says (what means): {…But if you are prevented, then [offer] what can be obtained with ease of sacrificial animals…} [Quran 2: 196]

Prevention, here, includes the one who was prevented by an enemy or due to any other reason, such as sickness, running out of money, etc. According to the preponderant opinion, he is not required to make up for the ‘Umrah that he was prevented from completing.

Allaah Knows best.