Getting a hold of Beyonce isn't easy, but Ed Sheeran managed to do it. 

ET's Keltie Knight caught up with the 26-year-old singer at KIIS-FM’s iHeartRadio Jingle Ball presented by Capital One at the Forum in Inglewood, California, on Friday, where he revealed how he was able to snag the superstar for a duet. 

"I have an email address I email [to get in touch with Beyonce]," Sheeran revealed, adding that the singer's email address "actually changes every week." "So I emailed that and we got on the phone, and it's been in the works since May." 

"Obviously she had twins [in June], and we finished [the song] in September, so I've been holding onto it since then," he continued of "Perfect," which was released on Thursday.  

According to Sheeran, Bey recorded the song in just one take -- and even had input on the track's instrumentals. 

"The original version of ‘Perfect’ was just an acoustic guitar and she rung me up and was like, ‘I don’t know how you feel about this but I’ve taken all the instruments off it and it's just gonna be acoustic guitar,’ and I was like, ‘Ah that’s great, because it used to be that!'" he revealed. "Then when we got in together, it wasn’t so much notes, it was very much like a back and forth thing, like, ‘What’d you think of this?' Or 'What do you think of this?’ and [we were] probably in the studio for four hours."

"She was just like, 'Right!' Went in, one take, came out, like, 'Yeah, that sounds alright!'" he confessed. 

See more on the duet in the video below. 

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