The 24-year-old actor, who met Darke on the set of his 2013 film 'Kill Your Darlings', was spotted doing grocery shopping with the actress in New York City last week, reported Ace Showbiz.
While shopping, Radcliffe wore a dark top, a cap and covered his eyes with sunglasses. Sporting a flowery dress, sunglasses and flat shoes, Darke was all smiles during the outing.
A representative for Darke confirmed that she and Daniel had been dating for "about two years."
Last year, Radcliffe and Erin were reportedly spotted getting cozy at the Sundance Film Festival.