Can I Perform hajj on behalf of someone else?

- Abdullah Ibn 'Abbas (may God be pleased with them both) narrated, "Al-Fadl Ibn 'Abbas was riding behind the Messenger of God and a woman from the tribe of Khath'am approached the Messenger with a question. Al-Fadl and the woman kept looking at each other so the Messenger of God turned al-Fadl's face to the other side. The woman said, ‘O Messenger of God! My father is an old man. He cannot sit firmly on his mount and therefore cannot perform his obligatory hajj. May I perform hajj on his behalf?' The Prophet replied, ‘Yes, you may.’ This was during the Farewell Pilgrimage.”1

- Abdullah Ibn 'Abbas (may God be pleased with them both) narrated, "The Messenger of God heard a man say, ‘O God! Here I am in response to your call on behalf of Shubrumah.’ The Prophet asked, ‘Who is Shubrumah?’ The man replied, ‘A brother or close relative. The Prophet asked, ‘Have you made your own hajj?’ ‘No,’ he replied. The Prophet said, ‘Perform your own hajj first and then perform it on behalf of Shubrumah."2

From the above two hadiths, it is evident that it is permissible for a person to perform hajj on behalf of another either voluntarily or for a fee provided he has performed his own obligatory hajj. It is likewise a condition that the person on whose behalf hajj will be performed is unable to perform it himself i.e. is deceased, suffers a broken body part, has a physical disability, a chronic disease, or is incarcerated with no hope of release. In one report from Hanafi scholars, the ruling is the same for a blind person. It is impermissible to perform hajj on behalf of a person who has a recoverable disease.
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1 Recorded by Bukhari (1538) and Muslim (3315).

2 Recorded by Abu Dawud (1813), Ibn Majah (3015) and Ibn Haban (3988). Ibn Khuzaymah declared it authentic (3039).