The magazine’s top writer was suspended last month following the video call with colleagues.
Mr Toobin, 60, confirmed his firing on Twitter after 27 years with the magazine.
“I was fired today by @NewYorker after 27 years as a Staff Writer. I will always love the magazine, will miss my colleagues, and will look forward to reading their work,” he wrote.
“I am writing to share with you that our investigation regarding Jeffrey Toobin is complete, and as a result, he is no longer affiliated with our company,” wrote Stan Duncan, Condé Nast’s chief people officer, to staffers in a memo, according to reports.
“I want to assure everyone that we take workplace matters seriously.
“We are committed to fostering an environment where everyone feels respected and upholds our standards of conduct.”
The bizarre incident occurred as staff at the magazine held an election simulation over Zoom with employees from WNYC radio station.
Mr Toobin, a legal analyst for CNN, was suspended after the incident and in a statement called it “embarrassingly stupid mistake" made when he thought he was not on camera.
“I made an embarrassingly stupid mistake, believing I was off-camera. I apologise to my wife, family, friends and co-workers,” he said.
“I believed I was not visible on Zoom. I thought no one on the Zoom call could see me. I thought I had muted the Zoom video."
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