The Messenger of Allah ﷺ said, "An Umrah performed in Ramadan equals a Hajj."
حدثنا أحمد بن عبد الملك حدثنا عبيد الله بن عمرو عن عبد الكريم عن عطاء
قال رسول الله ﷺ عمرة في رمضان تعدل حجة
Its isnad is sahih. Ubaydullah bin Amr is Raqqi, Abu Wahb, and Abdul-Kareem is Ibn Malik Jazari, and both are trustworthy. The hadith has already appeared at 14818.