Q: As a female Muslim, do I need a mahram to accompany on my trip to Hajj/Umrah?
A: The presence of a maḥram, such as a husband, father, or a nurse-relative etc. or anyone who is permanently impermissible to marry due to relation of some permissible cause like an in-law (this excludes impermissible causes such as a the mother of the woman one has committed adultery), is a condition of obligation of hajj and umrah for a female.
She must pay for the mahram.
The condition of provision and transportation for her includes both her and him.
He is not obliged to travel with her even though she is paying.
Without the mahram which she has commissioned, her travel will be impermissible based on the ḥadīth of Ibn Abbas, “A woman is not to travel except in the company of a mahram nor is a man to be with her except in the company of a mahram.” [Reported by Imam Ahamd]
There is no difference between a young woman and an old lady, long distances or short. If she does make hajj without a mahram it will suffice while sinful in nature.
If a woman has no mahram she is to appoint a proxy.
Source: Hidayat al-Raghib