كتاب الحج
11
The Book of Hajj
Abu Hurairah (May Allah be pleased with him) reported:
The Messenger of Allah (ﷺ) said, "(The performance of) 'Umrah is an expiation for the sins committed between it and the previous 'Umrah; and the reward of Hajj Mabrur (i.e., one accepted) is nothing but Jannah."

[Al-Bukhari and Muslim].

وعنه أن رسول الله صلى الله عليه وسلم قال‏:‏ ‏ "‏العمرة إلى العمرة كفارة لما بينهما، والحج المبرور ليس له جزاء إلا الجنة‏"‏ ‏(‏‏(‏متفق عليه‏)‏‏)‏
Sunnah.com reference : Book 11, Hadith 5
Arabic/English book reference : Book 11, Hadith 1275