Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
tirmidhi:3698 – Abū Hishām al-Rifāʿī > Yaḥyá b. al-Yamān > Shaykh from Banī Zuhrah > al-Ḥārith b. ʿAbd al-Raḥman b. Abū Dhubāb > Ṭalḥah b. ʿUbaydullāh

that the Messenger of Allah ﷺ said: "For every Prophet there is a friend (Rafiq), and my friend" - meaning in Paradise - "is 'Uthman."  

الترمذي:٣٦٩٨ – حَدَّثَنَا أَبُو هِشَامٍ الرِّفَاعِيُّ قَالَ حَدَّثَنَا يَحْيَى بْنُ الْيَمَانِ عَنْ شَيْخٍ مِنْ بَنِي زُهْرَةَ عَنِ الْحَارِثِ بْنِ عَبْدِ الرَّحْمَنِ بْنِ أَبِي ذُبَابٍ عَنْ طَلْحَةَ بْنِ عُبَيْدِ اللَّهِ قَالَ

قَالَ النَّبِيُّ ﷺ لِكُلِّ نَبِيٍّ رَفِيقٌ وَرَفِيقِي يَعْنِي فِي الْجَنَّةِ عُثْمَانُ  

قَالَ أَبُو عِيسَى هَذَا حَدِيثٌ غَرِيبٌ وَ لَيْسَ إِسْنَادُهُ بِالْقَوِيِّ وَهُوَ مُنْقَطِعٌ

See similar narrations below:

Collected by Ibn Mājah
ibnmajah:109 – Abū Marwān Muḥammad b. ʿUthmān al-ʿUthmānī > Abū ʿUthmān b. Khālid > ʿAbd al-Raḥman b. Abū al-Zinād from his father > al-Aʿraj > Abū Hurayrah

The Messenger of Allah said: "Every Prophet will have a friend in Paradise, and my friend there will be 'Uthman bin 'Affan."  

ابن ماجة:١٠٩ – حَدَّثَنَا أَبُو مَرْوَانَ مُحَمَّدُ بْنُ عُثْمَانَ الْعُثْمَانِيُّ حَدَّثَنَا أَبِي عُثْمَانُ بْنُ خَالِدٍ عَنْ عَبْدِ الرَّحْمَنِ بْنِ أَبِي الزِّنَادِ عَنْ أَبِيهِ عَنِ الأَعْرَجِ عَنْ أَبِي هُرَيْرَةَ

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ لِكُلِّ نَبِيٍّ رَفِيقٌ فِي الْجَنَّةِ وَرَفِيقِي فِيهَا عُثْمَانُ بْنُ عَفَّانَ