After 200+ hours, still couple things in game I don't really know why happens.

Not often, but not super rare - kinda semi-common, I will be walking around somewhere, totally not in combat or even remotely close to after combat - I will hear and see the sound/XP event popup message.

I thought at first maybe it was some enemy I wounded but didn't kill and something finished it off and I got xp credit. But that is definitely not it, I am hours or game day away from last combat, and will just get this xp ding.

Anyone know what event triggers this random award of xp?

Don't know why it happens, but it happens all the time for me too. Last night I suddenly got a message of 0700 XP and I wasn't doing anything but sitting on the balcony of my Sanctuary house.

I'd noticed a few times BoS gunship in the air and I get exp for their kills. Then I got in good with some other people and would see stuff for them too but mostly happens outside where there's npc battles of different factions and I don't think it happened at first nor is it supposed to happen unless I at least wound someone but I'm happy for some exp. You may also have idiot savant.

you don't have the perk Idiot Savant, do you?

Idiot savant doesn't give random XP. It has a chance to multiply XP that you get from conventional means.

I know what the OP is talking about, sometimes I randomly get like 40+ XP and sometimes I get a small little +7 XP. It's almost as if something out there is fighting and sharing the kill XP with me.

^^ yep what he said. I don't have idiot savant, and it's not huge xp or anything but anywhere from tiny to usually less than 100 xp, like 47 or some odd number like that usually.

Sometimes I will start a game session, have obviously never been in combat yet since I just booted game from the prior IRL day ago when last played, and will just be settlement crafting when I will get this random xp ding.

I have tried to kinda figure this out but posted because after 200+ hours, I'm pretty well versed in most good/bad things with FO4 but this one still stumps me.

Thought at first it was combat delay, that's not it. Nor friendly faction kills because with a new game session, factions haven't even loaded far as I know since I am in a cell very far away (e.g. my settlement, away from the brotherhood, etc). Then figured maybe I was getting some weird xp for a provisioner who was loaded near my area but couldn't see him because of terrain, and he had killed some random mob.

But I never get kills from friendlies giving me xp unless I assisted with at least 1 dmg against the enemy, so the prov killing stuff seems unlikely. And even then, I've had these dings when I am far, far away from any known supply line.

So basically stumped and no big deal or even tiny deal in terms of game play or impact. Just really, really curious what and why it is happening. I thought there was some obvious or behind the scenes answer.

I get these too usually when the BoS is around, and lately they turn up just about anywhere I go. I don't mind free exp but it is odd.

Happens all the time. My first suspects were settlers and provisioners killing stuff, but then I got XP after witnessing a raider kill something.

My current theory is that the game rewards XP to the player for kills on respawns of refs he killed before. You kill a Deathclaw, the Deathclaw respawns, a Raider kills the respawned Deathclaw, you get the XP. It probably happens because the flag to mark damage done by the player is set on the spawner, rather than the spawned object.

That sounds very plausible and very logical from where I'm standing.

+1 on your critical thinking skills, I never once even thought of such a thing. It would seem like a rookie mistake on Bethesda's part if that was what was happening.

Same here I get random XP I've never figured out why? But I'm not gonna complain either

It seems sometimes you get XP from enemies dying, even if you had no part in it (Or even knew there was an enemy nearby).

Exactly what I've been thinking about. I usually get random experience whenever I go to Hangman's Alley because of the super mutants nearby kept getting killed by my Provisioners (I've killed them once and Hangman's Alley is one of my major trading sections, with Red Rocket being my other. Though Red Rocket doesn't have any shops, it's primarily just 17 proviosners doing their jobs).