Fallout 4’s End User Licence Agreement states that all mods must be distributed for free.
Bethesda already tried the paid mods option with The Elder Scrolls V: Skyrim, and they were the first developer to take advantage of this in Valve’s Steam. It didn’t go well and they had to close it within a week, but now, they are doing the good thing from the start.
All Fallout 4 mods “must be distributed solely for free,” courtesy of NeoGAF user Gossi.
Fallout 4 releases on November 10 for the PS4, Xbox One and PC, so get ready, because that’s really soon.