The 40-year-old actor, who already has a one-year-old son called Christopher with Hunter, also spoke about how he’s finding fatherhood.
“We are expecting our second. I’m very excited,” he told This Morning’s Alison Hammond. “I’ll be there all the way, absolutely.”
Hammond asked Cumberbatch whether he felt being a dad was his “biggest achievement” in life.
“I think it’s Sophie’s biggest achievement,” he said. “I’m still trying prove myself as a dad.”
Cumberbatch has previously spoken publicly about wanting to expand his brood.
Shortly after the birth of his son, he said on the Graham Norton Show: “I have a new life form that needs his father’s help in the world and his mother needs a little help once in a while.
“It’s what being a parent is about, so it’s not an excuse to get away from what I am doing - it’s what I ought to be doing.
“I might go for a (Cumber)batch of boys!”
Fans were excited by the news of another potential #CumberBaby when E! News announced the couple were expecting on Friday 21 October. They took to Twitter with the hashtag to share the news.
‘This Morning’ is on ITV weekdays from 10.30am.