Since settler population is based on your charisma, you’re generally limited to round 20. However, Redditor /u/guilded_monkey has found a way to get 28 settlers with only a charisma level of 6. Here’s their step-by-step guide.
1) Set up a small settlement that functions as a recruitment center for the actual settlement (they used Hangman’s Alley). What until there are more people than you want in your actual settlement.
2) Equip items that give charisma bonuses.
3) Move people to the actual settlement. (To do this on PC, you just press R while in workshop mode – it’s basically like scrapping settlers.)
4) Take grape mentats, which will boost charisma (they reported a final level of 15 at this point).
5) Keep moving people to the actual settlement until the game stops you.
While a lot of it has to do with timing and luck, this trick should work. Please leave us a comment to let us know if you did anything differently to achieve the same effect!
If you liked this explainer, check out some of our Fallout 4 gameplay guides: increasing inventory space, changing your field of view, skipping the intro video, unlocking frame rate, which settings to turn on or off, basic and advanced console commands, and disabling mouse acceleration.