Ele recebeu o juramento de lealdade como califa três noites após o sepultamento de ʿUmar. Relata-se que, durante aqueles dias, as pessoas se reuniram com ʿAbd ar-Raḥmān ibn ʿAwf, aconselhando-o e conversando reservadamente com ele. Nenhuma pessoa de juízo que se sentou a sós com ele viu alguém igual a ʿUthmān. Quando ʿAbd ar-Raḥmān se sentou para receber o juramento de lealdade, louvou a Allah e disse, em seu discurso: "Vi que as pessoas recusam qualquer outro que não seja ʿUthmān." Ibn ʿAsākir narrou isso de al-Miswar ibn Makhramah. Em outra narração: "Agora! ʿAlī, pesquisei entre as pessoas e não as vejo considerando alguém igual a ʿUthmān. Portanto, não abras um caminho contra ti mesmo." Tomou a mão de ʿUthmān e disse: "Juramos lealdade a ti segundo a Sunnah de Allah, a Sunnah de Seu Mensageiro e a Sunnah dos dois califas depois dele." ʿAbd ar-Raḥmān prestou-lhe juramento de lealdade, e os Muhājirūn e os Anṣār também lhe prestaram juramento de lealdade.

He was pledged allegiance as khalifah three nights after the burial of cUmar. It is related that people got together, during those days, with cAbd ar-Rahman ibn cAwf, advising him and talking confidentially with him. Not one person of judgement who sat alone with him saw any to equal cUthman. When cAbd ar-Rahman sat to pledge allegiance, he praised Allah and said, during his speech, ‘I saw that people refuse anybody but cUthman.’ Ibn cAsakir narrated it from al-Miswar ibn Makhramah. In another narration, ‘Now! cAli, I have researched among people and I don’t see them regarding anyone equal to cUthman. Therefore, do not make a way against yourself.’ He took the hand of cUthman and said, ‘We pledge allegiance to you according to the Sunnah of Allah, the Sunnah of His Messenger and the Sunnah of the two khalifahs after him.’ cAbd ar-Rahman pledged allegiance to him and the Muhajirun and the Ansar pledged allegiance to him.

Ibn Sa'd narrou que Anas disse: Umar mandou chamar Abu Talha al-Ansari uma hora antes de morrer e disse: "Você estará entre cinquenta dos Ansar junto com este grupo, os companheiros do conselho, pois eles, como acredito, se reunirão em uma casa. Fique naquela porta com seus companheiros, não permita que ninguém entre, e não os deixe permitir que o terceiro dia passe sem que eles escolham um deles para o comando." No Musnad de Ahmad há o relato de que Abu Wa'il disse: Perguntei a Abd ar-Rahman ibn Awf: "Como pôde jurar lealdade a Uthman e negligenciar Ali?" Ele respondeu: "Onde está o meu erro? Comecei com Ali e disse: 'Devo jurar lealdade a você de acordo com o Livro de Allah, a Sunnah de Seu Mensageiro ﷺ e a conduta de Abu Bakr e Umar?' Ele disse: 'Naquilo que eu for capaz.' Depois, ofereci o mesmo a Uthman, e ele disse: 'Sim.'" Foi relatado que Abd ar-Rahman disse a Uthman em particular: "Se eu não jurar lealdade a você, a quem você me indicaria?" Ele disse: "Ali." Disse a Ali: "Se eu não jurar lealdade a você, a quem você me indicaria?" Ele disse: "Uthman." Então ele chamou az-Zubayr e disse: "Se eu não jurar lealdade a você, a quem você me indicaria?" Ele disse: "Ali ou Uthman." Depois, chamou Sa'd e disse: "A quem você me indicaria?"

Ibn Sacd narrated that Anas said: cUmar sent for Abu Talhah al- Ansari an hour before he died and said, ‘You be among fifty of the Ansar along with this group, the companions of the counsel, because they, as I believe, will gather in a house. Stand at that door with your companions, allow no-one to enter, and do not leave them to allow the third day to pass without their appointing one of themselves to the command.’ There is in the Musnad of Ahmad that Abu Wa’il said: I said to cAbd ar-Rahman ibn cAwf, ‘How could you have sworn allegiance to cUthman and neglected cAli?’ He said, ‘Where was my wrong action? I started with cAli and I said, “Shall I swear allegiance to you according to the Book of Allah, the Sunnah of His Messenger and the conduct of Abu Bakr and cUmar?” He said, “In what I am able.” I hen later I offered the same to cUthman and he said, “Yes.”’ It has been related that cAbd ar-Rahman said to cUthman in private, ‘If I don’t pledge allegiance to you who would you point out to me?’ He said, ‘cAli.’ He said to cAli, ‘If I don’t pledge allegiance to you who would you point out to me?’ He said, ‘cUthman.’ Then he called for az-Zubayr and said, ‘If I don’t pledge allegiance to you who would you point out to me?’ He said, ‘cAli or cUthman.’ Then later he called for Sacd and said, ‘Whom would you indicate to me?

"porque, quanto a mim e a você, não o queremos." Ele disse: "'Uthman." Então cAbd ar-Rahman buscou o conselho de todos os notáveis e viu que a maioria deles se inclinava para cUthman.

because, as for me and you, we don’t want it.’ He said, ‘'Uthman.’ Then cAbd ar-Rahman sought the counsel of all the notables and saw that most of them were inclined to cUthman.

Ibn Sa'd e al-Hakim narraram que Ibn Mas'ud, que Allah esteja satisfeito com ele, disse, quando 'Uthman recebeu o juramento de lealdade: "Encarregamos do comando o melhor dos que restaram, e não fomos negligentes." Neste ano de seu califado, Ray foi conquistada [para o Islam]; ela já havia sido conquistada anteriormente e depois perdida. Naquele ano, muitas pessoas tiveram hemorragias nasais, de modo que ficou conhecido como "o ano das hemorragias nasais". 'Uthman também foi acometido por hemorragias nasais a tal ponto que se ausentou do Hajj e designou alguém em seu lugar. Naquele ano, muitas fortalezas bizantinas foram tomadas. Nele, 'Uthman nomeou Sa'd ibn Abi Waqqas governador de Kufa e destituiu al-Mughirah.

Ibn Sacd and al-Hakim narrated that Ibn Mascud, may Allah be pleased with him, said, when cUthman was pledged allegiance, ‘We have charged with command the best of those remaining and we have not been negligent.’ In this year of his khilafah, Rayy was opened [to Islam], and it had been opened previously and subsequently lost. In that year many nosebleeds occurred among people, so that it was known as, ‘The year of the nosebleeds.’ cUthman was afflicted by nosebleeds to such an extent that he stayed away from the Hajj and deputed someone in his place. In that year many Byzantine fortresses were taken. In it cUthman appointed Sacd ibn Abi Waqqas as governor of Kufa and removed al-Mughirah.

In the year 25 AH, ʿUthmān removed Saʿd from Kufa and appointed al-Walīd ibn ʿUqbah ibn Abī Muʿayṭ, and he was a Companion and a brother of ʿUthmān on his mother's side; and that was the first thing for which he was disliked, because he appointed his relatives to posts of authority. It has been told as a tale that al-Walīd led them in prayer for the dawn prayer with four rakʿāt when he was drunk, and that then he turned to them and said, ‘Shall I do more (rakʿāt) for you?’ In the year 26 AH, ʿUthmān enlarged and extended al-Masjid al-Ḥarām, and bought sites (adjoining it) for the enlargement. In the same year Sābur (possibly Shāhpūr) was opened.

In the year 25 AH, cUthman removed Sacd from Kufa and appointed al-Walid ibn cUqbah ibn Abi Mucayt — and he was a Companion, and a brother of cUthman on his mother’s side - and that was the first thing for which he was disliked; because he appointed his relatives to posts of authority. It has been told as a tale that al-Walid led them in prayer for the dawn prayer with four rakcfat when he was drunk, and that then he turned to them and said, ‘Shall I do more (raka?at) for you?’ In the year 26 AH, cUthman enlarged and extended al-Masjid al-Haram, and bought sites (adjoining it) for the enlargement. In the same year Sabur (possibly Shahpur) was opened.

No ano 27 AH, Muawiyah realizou uma expedição militar a Chipre, levando os exércitos por mar. Ubadah ibn as-Samit estava com eles, assim como sua esposa, Umm Haram bint Milhan al-Ansariyah (das Ansar). Ela caiu de sua montaria e morreu ali como mártir, e o Profeta ﷺ havia anunciado este exército para ela. Ele havia suplicado por ela para que ela fosse incluída entre eles. Ela foi sepultada em Chipre. Naquele mesmo ano, Arrajan e Darabjird foram conquistadas. Uthman destituiu Amr ibn al-As do Egito e nomeou Abdullah ibn Saad ibn Abi Sarh para governá-lo, o qual liderou uma expedição contra o norte da África e a abriu [ao Islam], tanto nas planícies quanto nas montanhas, e cada homem do exército recebeu mil dinares, e também foi dito que três mil dinares. Em seguida, Andaluzia foi conquistada neste mesmo ano.

In the year 27 AH, Mucawiyah went on a military expedition to Cyprus, taking the armies by sea. cUbadah ibn as-Samit was with them and his wife, Umm Haram bint Milhan al-Ansariyah (of the Ansar). She fell from her riding beast, and died there as a martyr, and the Prophet, may Allah bless him and grant him peace, had foretold this army for her. He had supplicated for her that she should be of them. She was buried in Cyprus. In that same year Arrajan and Darabjird were opened. cUthman removed cAmr ibn al-cAs from Egypt and appointed cAbdullah ibn Sacd ibn Abi Sarh over it, who led an expedition against northern Africa and opened it [to Islam], both on the plains and in the mountains, and every man in the army received one thousand dinars, and it has also been said, three thousand dinars. Then Andalusia was opened in this same year.