The 24-year-old 'Someone Like You' singer gave birth to a baby boy on Friday, October 19, a family source confirmed with People magazine.
"We are all over the moon," the source said.
Adele and boyfriend, UK charity founder Simon Konecki, are yet to announce the baby's name.
The popular chanteuse announced her pregnancy on her blog in June.
"I'm delighted to announce that Simon and I are expecting our first child together," she wrote.
"I wanted you to hear the news direct from me, obviously we're over the moon and very excited but please respect our privacy at this precious time. Yours always, Adele xx."
While it's the first bub for Adele, her 38-year-old partner has a five-year-old daughter from a previous marriage.
The couple have been dating since late last year. They have denied multiple rumours that they are secretly married.
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