Knowles joined the famous weekly music newspaper in 2000 as the NME's youngest editor at the age of just 26. He joined from the now defunct Melody Maker, NME's former stablemate at publisher IPC Media.
Knowles has no job to go to when he leaves the paper, but he claims to have been offered "some interesting journalism work", as well as wanting to "take some new opportunities in radio and TV".
Knowles's decision to leave IPC comes in the NME's 50th anniversary year, the same year that the paper lost its lead to Emap's rock and nu-metal magazine Kerrang. NME recorded an ABC of 70,456 in the last audited period, a slight increase on the previous period, but trailed Kerrang's 76,841.
Knowles took over the editorship from Steve Sutherland, who is now editorial director of the title.
According to Sutherland: "Ben came to see me earlier this year to say he wanted to move on, but I asked him to stay in charge until the NME Awards were over, the 50th Anniversary souvenir issue was complete and to oversee the NME's change to its new format. Having led these projects to enormous success, he departs with our very best wishes for the future."
Sutherland is expected to oversee the editorial department until a successor is appointed.
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