“Bey and Jay are thrilled and have started sharing the news with their family and closest friends,” a source told People, who reported the arrival on Saturday.
Beyoncé, 35, and Jay Z, 47, are already parents to 5-year-old daughter Blue Ivy.
Beyoncé revealed she was expecting twins via social media in February.
“We would like to share our love and happiness,” the songstress captioned a photo of herself in lingerie holding her growing belly, “We have been blessed two times over. We are incredibly grateful that our family will be growing by two, and we thank you for your well wishes. – The Carters.”
Reps for Beyoncé and Jay Z did not immediately return requests for comment.