Which News Network is the least biased?

Reuters is probably the least biased. But they are a News Gathering service, not a reporting service.

It depends whether you are talking about the US or the world. Fox is fiction. CNN gives facts but is biased against Trump, for good reason. BBC is good for world and European news. Al Jazeera is a very fair news channel with a lot of reporters around the world. RT is russian propaganda. I read a number of them to get a balanced view. 

They're all biased.  And since journalism is an inherently left-wing profession, most of big outlets are severely biased to the left.  You just have to find the one that best fits your bias, and being a centrist counts as having a bias.  Nobody ever said you have to be completely conservative or liberal, you're allowed to be both.

BBC, Time, Reuters, USA Today and the almost unreadable Wall Street Journal are pretty solid in the center of the spectrum.  CNN, CBC, MSNPC and Guardian are all cheerleaders for the loony left.  FOX, Sun Media, NY Post and Washington Times cater almost exclusively to the Guns & Jesus crowd.  

Then there's the real nut jobs, which exist on both sides of the fence.  Places like Huffington Post, InfoWars, Vox and Breitbart are all considered pure propaganda, even by most liberals and conservatives.

FOX News won awards and is rated the most honest news source.

Even though the ones you mentioned all have left wing bias, Fox has the least left wing bias.

You mean TV news only. Then I would say BBC. Or NPR. [National Public Radio] but I think the NY Times is really good.

PBS, I guess.  But all networks are biased. CNN is probably the worst.

You DO know there are other news networks in the USA, "the only country that matters to you", right?  CBC does a good job.  So does BBC, and al-Jazeera.

I wouldn't trust ANY of them to be honest.

Reuters is the best I've found.