Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) was asked how many Umrahs the Messenger of Allah (peace and blessings be upon him) performed, and he said: Two. Sayyidah Aishah (may Allah be pleased with her) said: Ibn Umar (may Allah be pleased with them both) knows that the Messenger of Allah (peace and blessings be upon him) performed three Umrahs besides the one that he combined with his Hajj.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 8835