His wife Sophie Hunter gave birth to a baby boy on Saturday (13 June).
A spokesperson for the pair told The Sun: "Benedict Cumberbatch and Sophie Hunter are delighted to announce the arrival of their beautiful son.
"We would kindly ask everyone to respect the family's privacy during these next few precious weeks."
Benedict and Sophie first announced their engagement in a notice in The Times newspaper in November last year, having met when they appeared together in the 2009 film Burlesque Fairytales.
The Sherlock star, 38, then married actress Sophie in a private ceremony on the Isle of Wight on Valentine's Day this year, one month after confirming they were expecting a baby.
At the time, a spokesperson said: "I am delighted to confirm that Benedict Cumberbatch and Sophie Hunter are expecting their first child. They are both over the moon."
It's turning out to be an amazing month for actor Benedict as it was announced this week that he's been given a CBE in the Queen's birthday honours list for his services to drama.
Double congratulations to Benedict and his wife!
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