While defending himself in the "Thinking Out Loud" copyright lawsuit, Ed Sheeran was asked to hand over his old electronic devices. This included a smartphone he'd switched off in December 2015. When he turned it on again, the phone coughed up a digital avalanche: unread texts, forgotten photos, ghostly remnants of a previous life. The first message was from his late friend, Jamal Edwards. The second from an ex-girlfriend. The third from a long-lost family member. Each ping a small, piercing echo from the past. Sheeran described the experience as "stepping into a time machine," finding himself scrolling through conversations with people who were no longer in his life, either due to loss or drifting apart. The emotional impact of this digital time capsule led him to write "Old Phone" alone at 2 a.m. while jet-lagged in India, where he was finishing his Play album.

"Old Phone" is Sheeran at his most Sheeran: strumming like a campfire bard, balancing heartbreak with cozy sentiment. He mourns the drift of time, lost friends, family fallouts, the melancholy weight of growing up, wrapping it in a warm, rollicking acoustic arrangement.

Sheeran co-produced the song with Ilya Salmanzadeh (Ariana Grande, Tate McRae) and Blake Slatkin (The Kid Laroi, Lizzo). It was Sheeran's first release with Slatkin, although he and Ilya had previously teamed up on Play's lead single, "Azizam."