The shocking romance comes just week after the reality hunk broke off his engagement to show fiancé Vanessa Grimaldi.
According to a Page Six source, Jones and Viall got together after she told show host James Corden that she was a Bachelor super-fan.
"You don't know if you like him or if he's a scumbag, but that's why I'm attracted to him, maybe," January Jones said of now-boyfriend Nick Viall at the time.
After the show, the newly-single star asked the blonde beauty out – and the rest is history!
"They've been dating for about two months. She went on 'The Late Show' in mid-November and said Nick had reached out to her and tried to get her to lip-sync battle with him. She declined, but then he asked her out to a drink and she accepted. They've been seeing each other since," the source told Page Six.
The actress reportedly even celebrated her 40th birthday with Viall, 37, and other pals this past Saturday in Los Angeles.
Are you surprised Nick Viall has already moved on, and is now dating January Jones? Sound off in the comments below.
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