Do I need to watch Blade Runner before watching Blade Runner 2049?

The director says it's not necessary to see Blade Runner first

Director Denis Villeneuve said that he intended for it to be accessible to first time viewers.

"That was one of the challenges ... to create a movie that would be in total relationship to the first one, but could stand on its own," he said when we met to discuss the film in London recently. "I will say that people don't need to see the first movie to understand my movie."

_{—"Do I need to watch 'Blade Runner' before seeing the sequel?", CNET, October 4, 2017 (Emphasis mine)}

But he thinks you should see it anyway because it's really good

"I would recommend [seeing] the first movie because I think it's a masterpiece," Villeneuve says. "One of the things I said to myself that could be a positive effect of doing [the sequel] is to to put back the spotlight on the original movie, for the generation that are too young to have seen it on a big screen or even at home.

_{—"Do I need to watch 'Blade Runner' before seeing the sequel?", CNET, October 4, 2017}

Either the Theatrical Cut or Final Cut is sufficient

Villeneuve has said that the Theatrical Cut and Final Cut have different thematic elements and Blade Runner 2049 is "in between" (minor spoilers):

"The key to making [Blade Runner 2049] was to be in between," Vileneuve said. "[The theatrical version] is the story of a human falling in love with an artificial being, and the story of [the director's cut] is a replicant who doesn’t know he’s a replicant and slowly discovers his own identity. Those are two different stories."

_{—"Which Cut Is Blade Runner 2049 a Sequel To?", Den of Geek!, August 25, 2017}

CNET's Richard Trenholm says you can watch either, since the major plot difference isn't critical to the sequel.

In terms of getting ready for the sequel, either would work. Fans deride the Theatrical Cut for its over-explaining voiceover and studio-imposed happy ending, but it still packs a punch if that's the only version you have access to. The Final Cut removes the voiceover and, more importantly, creates ambiguity around who is or isn't an android -- but that theme isn't critical to the sequel, so the choice is yours.

_{—"Do I need to watch 'Blade Runner' before seeing the sequel?", CNET, October 4, 2017}

GQ's Scott Meslow recommends the Final Cut because the original director, Ridley Scott, personally oversaw it.

So there are like 27 versions of this movie, right? How many of them do I actually need to watch?

Just one! And Ridley Scott made it pretty easy to remember, because it’s the one called Blade Runner: The Final Cut. After years of confusion about the "real" version of Blade Runner, The Final Cut was released in 2007 to provide a single, definitive of Blade Runner. Scott personally oversaw a brand-new remaster of the original movie.

_{—"Everything You Need to Know About Blade Runner Before Blade Runner 2049", GQ, September 28, 2017}

I haven't seen any recommendations to watch both before seeing Blade Runner 2049, unless you are personally interested in seeing the difference.

If you don't have time to watch the original, you can watch some short prequel films

There are three short films created as prequels to Blade Runner 2049 in order to promote the film and expand on the world. If you just want to get a sense of what the world is like, this is a good jumping on point.

• 2036: Nexus Dawn (live action, 6:30)
• 2048: Nowhere to Run (live action, 5:47)
• Blade Runner Black Out 2022 (animated, 15:48)

After watching the movie I have to say that to get the full experience from the movie you absolutely have to watch the original (I watched the Final Cut) and the three short films that were released this year.

Thing is: a lot of major plot-points revolve around the events of these other products in a big way for the original movie and smaller but mutually enriching for the shorties.

I hope you didn't go out there unprepared for the BR 2049 because otherwise you risk to not only understand but build up a required emotional attachment to certain characters.

The fact that the director Denis Villeneuve said that "it's not necessary to watch the original" is probably based around the fears that it might scare off people with it's slow pacing and vagnuess which ironically the new picture inherits. But fret not! The new movie is polished enough to be enjoyable from the get go and provides all the necessary information (unlike the old picture) to understand the plot assuming that you've watched all there is to watch and paid attention.