Is there an age at which a woman no longer needs a mahram?

Praise be to Allah.

Firstly: 

Hajj is only obligatory for those who are able to do it, because Allaah says (interpretation of the meaning): 

“And Hajj (pilgrimage to Makkah) to the House (Ka‘bah) is a duty that mankind owes to Allaah, those who can afford the expenses”

[Aal ‘Imraan 3:97]

One of the conditions of being able to do it for a woman is that she should have a mahram who agrees to go with her. If she cannot find a mahram then she is not obliged to perform Hajj. 

It says in Fataawa al-Lajnah al-Daa’imah (11/93): One of the conditions of Hajj being obligatory is that one should be able to do it, which includes having a mahram for women. If a woman does not have a mahram then she is not permitted to travel, and she is not obliged to perform Hajj unless she has a mahram and he agrees to travel with her. Allaah says (interpretation of the meaning): 

“And Hajj (pilgrimage to Makkah) to the House (Ka‘bah) is a duty that mankind owes to Allaah, those who can afford the expenses”

[Aal ‘Imraan 3:97]

See also questions no. 316, 5207 and 34380. 

Secondly: 

There is no age at which a woman does not need a mahram, rather at all ages of her life after she reaches puberty it is not permissible for her to travel without a mahram. No distinction is made between young women and old women, because the Prophet (peace and blessings of Allaah be upon him) said: “No woman should travel except with a mahram.” Narrated by al-Bukhaari and Muslim. 

We have explained this in the answers to questions no. 47029 and 25841. 

Thirdly: 

If a woman has a mahram, she has to spend on him.  

Ibn Qudaamah (may Allaah have mercy on him) said: 

She has to spend on her mahram’s expenses during Hajj, as was stated by Ahmad, because this is part of her being able to perform Hajj. So she has to spend on his expenses such as travel. Based on this, part of her ability to perform Hajj is that she should be able to afford provisions and travel expenses for herself and for her mahram. 

Al-Mughni, 3/99 

Al-Sarkhasi said: 

If a mahram travels with her then she should spend on him from her own wealth. 

Al-Mabsoot, 4/163 

Fourthly: 

With regard to your delaying Hajj because you need the money, please see question no. (11534). 

And Allaah knows best.