To perform Hajj on behalf of a dead person. A man can perform Hajj on behalf of a woman

Sahih al-Bukhari · Book 28 · Hadith 1852

حَدَّثَنَا مُوسَى بْنُ إِسْمَاعِيلَ، حَدَّثَنَا أَبُو عَوَانَةَ، عَنْ أَبِي بِشْرٍ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ ـ رضى الله عنهما ـ أَنَّ امْرَأَةً، مِنْ جُهَيْنَةَ جَاءَتْ إِلَى النَّبِيِّ صلى الله عليه وسلم فَقَالَتْ إِنَّ أُمِّي نَذَرَتْ أَنْ تَحُجَّ، فَلَمْ تَحُجَّ حَتَّى مَاتَتْ أَفَأَحُجُّ عَنْهَا قَالَ ‏"‏ نَعَمْ‏.‏ حُجِّي عَنْهَا، …

Narrated Ibn `Abbas: A woman from the tribe of Juhaina came to the Prophet (ﷺ) and said, "My mother had vowed to perform Hajj but she died before performing it. May I perform Hajj on my mother's behalf?" The Prophet (ﷺ)…