I just read about a settlement with a population of 40.

I'm level 43 and my biggest settlement, Sanctuary, has only 9 settlers. Mostly my companions.

I build recruitment beacons at every settlement that I can. Nobody seems to show up. (Yes, they're activated. I've listened to them on the radio.) I have plenty of spare beds, food and water capacity.

Why does nobody want to join my settlements? What am I doing wrong?

Your settlement population is related to your charisma level.

you charisma can be affected by your point allocation, the clothes you wear and temporary boosting by drugs and alcohol.

for instance to get 35 settlers at a settlement i wore a hat, glasses and suit that boosts my basic (10 I think) charisma.

Then took some alcohol and drugs that stacked to boost my charisma while i sent settlers to that settlement from other settlements.

Population limit is 10+charisma. At least that's the main theory.

Most of my settlements plateau out at 21/22 when I max out charisma and add the bobblehead. (I don't bother beyond that) BUT, I have had settlements occasionally bug out and attract more. One reached 38, which was annoying as it was one of the smaller, limited ones and there wasn't enough space for that many beds.

If someone has reached 40 settlers, then they have either bugged out or they are using a mod to unlock the limit.

My raw charisma is 9, I usually wear sunglasses and a hat to raise it to 11.

I've also tried to send settlers to Sanctuary, but the option I get is to set up a supply line? Or is that what actually sends a settler to a different settlement?

Isn't there also an unemployment limit? If you have more than four or five or so without jobs you won't attract any more, or something like that is what I heard. I don't build big highly populated settlements for the most part. I think my biggest settlement at the moment has like fourteen people.

Edit: You send people to another settlement with the 'Move' option.

No setting up a supply line doesn't move the settler.

When you write that the option you get is to set up a supply line does that mean that the option to move is greyed out or not there at all?

To send a settler to a full settlement you boost your charisma just before sending them.

Graqe mentats give a +5 boost i think.

Actually come to think of it I'm not sure if you can send a settler to a settlement that you aren't connected to with a supply line as I've never tried it.

Someone else might know or you could do a hard save and test it out yourself.

For me it's like this in workshop mode.

With the settler highlighted you can command them, move them, or assign them to a supply line.

http://ocau.com/pix/60cyh

When you select move another menu comes up of the available destinations.

for me if a destination is greyed out it's because it's at capacity so i then boost my charisma sufficiently to temporarily overcome the limitation.

Like taking graqe mentats and drinking a brew as my outfit is always the same charisma boosting level. Suit, hat and glasses.

I was given the option to move the settler, but then all that happened was that a supply line was set up.

You seem to be saying that the supply line has to come first, before settlers can move between settlements... I guess I need to go back to some settlements and see if I can now send settlers up the supply line.

I'm still frustrated by how few show up for the recruiting beacons, though. As fast as raiders and mutants spawn, I'd hoped that settlers would have at least some rate of reproduction.