An elderly woman who is permanently unable to perform الحج — due to old age, chronic illness, or physical disability that prevents travel — may appoint a proxy (na'ib) to perform الحج on her behalf. This is agreed upon by all four schools of jurisprudence and is based on the explicit hadith where a woman asked النبي about الحج for her elderly father who could not sit firmly on a mount, and النبي permitted proxy الحج.
الشيخ ابن باز stated that the condition for appointing a proxy is that the inability must be permanent — the person must have no reasonable expectation of recovery. Temporary illness does not justify proxy الحج; the woman should wait until she recovers. If the elderly woman has the financial ability but cannot physically perform الحج, the obligation remains and must be fulfilled through a proxy. She should pay for the proxy's expenses from her own wealth.
الشيخ ابن عثيمين clarified that the proxy may be male or female, and should have already completed their own واجب الحج. The proxy makes the intention specifically on behalf of the elderly woman at the الميقات: 'Labbayk on behalf of [her name].' The proxy performs all the rites exactly as they would for their own الحج. If the elderly woman passes away before a proxy is sent, her heirs should arrange for proxy الحج from her estate if she had the financial means during her lifetime.