Errol Barnett traveled to all parts of Africa for his award-winning show, Inside Africa. He also worked on shows like Global Exchange, African Voices, and CNN Marketplace Africa that were all based in Johannesburg, South Africa. While working there, Barnett covered the death of President Nelson Mandela, illegal mining strikes, the murder of Oscar Pistorius, and many other significant stories. He was profiled in May 2013 in GQ South Africa and interviewed about his journeys. He has also anchored the show, Prism at CNN Abu Dhabi and weekend shows like World Report and iReport for CNN.

Barnett later relocated back to Atlanta, Georgia. While still working for CNN International, he anchored coverage of the Ferguson, Missouri protests, the death of Robin Williams, and the search for the MH370. “Somehow, I've been fortunate enough to leave one dream job for another”, he wrote in his official biography.

On September 21, 2015, Erroll Barnett announced to the CNN audience that he had finally become an American citizen. He is a proud member of the National Association of Black Journalists, “I'm an optimistic, multinational, millennial with more ideas about the future than I know what to do with. I've worked my way up from being a gap-toothed kid in Milton Keynes, England to a position I never imagined; reporting from the American capital for the most-watched broadcast network in the country. Those who've beaten the odds inspire me and in many ways, helped me try to do the same.”

In June 2016, he joined CBS News as a Washington, D.C.-based correspondent and started appearing on CBS This Morning, the CBS Evening News and on the digital network CBSN. On his last appearance with the CNN network, CNN anchor Rosemary Church sent him off saying. "He is amazing, I’m going to miss him so much, you are going to shine as you take this next step along your career path. You're going to shine". Barnett replied, "CNN hired me after graduating from UCLA. I was lucky at that. I was fortunate enough to be sent to the Middle East, throughout Africa. It’s because of everything I’ve done here that I’m able to go to a dream job in Washington.”

Barnett also worked at ReelzChannel between July 2006 and June 2008, "I worked as a correspondent and host for the network's movie news program "Dailies" and several other feature specials, covering headlines from the movie industry took me from New York to Hawaii, and from film festivals to movie sets."

During his career, Barnett has made a tremendous impact on younger generations through his work on socially conscious stories. He has also covered stories like the formation of the anti-piracy legislation in Britain and France, the presidential elections in South Africa, Afghanistan and Israel, and the international reaction to US President Barack Obama being given the Nobel Peace Prize in 2009.

Barnett moderates panel discussions on a regular basis and gets invited to speak at numerous conferences on topics such as innovation in journalism and U.S. politics. In August 2014, Errol became an Internet sensation because of his response to his co-anchor's suggestion that police use water cannons on demonstrators. Buzzfeed described Barnett's reaction as “did that just happen” and “is this real life?” and the resulting memes went viral.