According to Pete Hines of Bethesda, Fallout 4 DLC doesn’t require a certain completion rate. You don’t have to end the game or be at a certain point in story to be able play the DLC.
He revealed that it adds to your existing experience so it doesn’t really matter where you are and what you’re doing.
@KevinWelge doesn't really matter. adds into your existing experience regardless of where you are and what you've done
— Pete Hines (@DCDeacon) February 16, 2016
Fallout DLC has been the talk of the town for past 24hrs, ever since Bethesda announced a price increase. Bethesda raised the price of Fallout 4 Season pass from $39.99 to $49.99 for those who don’t already own it. The price change will take effect from March 1, so if you plan on getting the season pass for Fallout 4, now is the time.
Obviously, fans weren’t happy but Pete Hines explained how this change is justified.
Fallout 4 Season Pass will bring you three pieces of DLC – Automatron, Wasteland Workshop, Far Harbor. Each will bring unique elements/features as well as some story to the game.
You can go ahead and read up on Fallout 4 DLC details.
You can get the season pass on PlayStation 4, Xbox One and PC.