This will be the couple's first child and they are said to be "over the moon" by their exciting news.
Announcing their baby joy in a statement, the Sherlock star's rep said: "I am delighted to confirm that Benedict Cumberbatch and Sophie Hunter are expecting their first child. They are both over the moon."
Whispers of a suspected pregnancy began swirling on the weekend, after Sophie was spotted on the red carpet with a rounded tummy.
The couple were pictured at the Palm Springs International Film Festival on Saturday and Sophie was wearing a patterned floor-length Just Cavalli maxi dress with matching belt detail.
To add to the rumours, she made sure to place her clutch bag right over her growing bump. Very clever!
It's been an exciting time for the couple recently, as they have got engaged too.
In November, Benedict and Sophie announced their engagement by taking out an advert in The Times newspaper.
Eagle-eyed fans who had spotted the announcement applauded the couple for their "classy" and "discreet" way of sharing the news.
Congratulations again, guys!
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