An elderly woman who is permanently unable to perform Haji — due to old age, chronic illness, or physical disability that prevents travel — may appoint a proxy (na'ib) to perform Haji on her behalf. This is agreed upon by all four schools of jurisprudence and is based on the explicit hadith where a woman asked Nabi about Haji for her elderly father who could not sit firmly on a mount, and Nabi permitted proxy Haji.
Sheikh Ibn Baz 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 Haji; the woman should wait until she recovers. If the elderly woman has the financial ability but cannot physically perform Haji, the obligation remains and must be fulfilled through a proxy. She should pay for the proxy's expenses from her own wealth.
Sheikh Ibn Uthaymeen clarified that the proxy may be male or female, and should have already completed their own wajib Haji. The proxy makes the intention specifically on behalf of the elderly woman at the miqat: 'Labbayk on behalf of [her name].' The proxy performs all the rites exactly as they would for their own Haji. If the elderly woman passes away before a proxy is sent, her heirs should arrange for proxy Haji from her estate if she had the financial means during her lifetime.