This has always confused me since information floating around online has been so conflicting. So I'm here to ask questions, clear up some answers with the knowledge I already possess (unless it's wrong so throw tomatoes), and get to the bottom of this once and for all.

What is the Maximum Sim Count?
Maximum Sim Count is how many Sims you can have in The Sims 4. The default setting is 80. Other options the game allows you to choose are 150, 200 (Max Recommended), and Unlimited.

Why is this needed?
In a nutshell, this Sim Count protects your played households/Sims from being culled by the game when the population starts overgrowing like rabbits. It also stops the game from slowing down and crashing (more so than it already does shots fired) especially if your machine is a potato.

Does the Maximum Sim Count only count number of played households? Or all played Sims?
All played Sims. So for example, if you have two households, one with 3 adults and a pet, and another with 2 adults and 2 children, then this counts as 8 Sims in total. Yes, pets count.

That's not very much room considering there's about a thousand expansions and worlds and bugs.
Exactly. If you play with only the default amount, with all expansions, you'll find your worlds begin to feel quite barren if you're working within the active Sim limit and tend to play large families. Unless you love those procedurally generated townies with their clown afros and Jerusalem cruisers (sandals).

So who gets deleted exactly and who doesn't? If I play as a random Townie will they be at risk of deletion once past the threshold?
Townies the game creates don't count towards your Maximum Sim Count. These are the Sims that get deleted or 'culled' once your Active Household Sims surpass your Maximum Sim Count limit. Any households or Sims that are 'favourited' with the little heart icon and put into your 'My Households' tab are safe from being culled. If you love that one Townie, this is the place they need to be, so hit that heart button!

How do I know what Sim Count my machine can handle?
Very good question. This is the kicker. Some people know their machines are more lower end so keep to an 80-150 limit. Others go full blown Unlimited and have around 300+ Sims with some reporting lag, some that don't. You need to experiment and get a feel for what number is right for you.

So Unlimited is Unlimited. But surely the game has a max limit coded for stability reasons?
Absolutely. Now this is my problem.

With all that out of the way, I want to ask about this secret number in the background of the game. Apparently, the secret number is 575 from what I can glean from various threads floating around the internet. Sometimes this number changes, (550 - 525) but apparently it's been said the number grows with each added expansion. I'm not quite a code monkey, so I can't verify this. I'd love it if someone could do that for me. So that leaves the question of just how many Sims is too many before the game becomes unplayable.

Do you have more than 200 Sims and notice any lag? Do you purposefully keep within the 200 Max Recommended set by Maxis? Or do you just not care about this whatsoever and play the game unlike me who has been driven crazy by this number and wants to know what exactly the consequences are in surpassing it?

Let me know! I hope someone finds this helpful out there.

I use mccc to stop all the culling. That said, I have mine set at Unlimited. I have often had the sim count be in the high 500s. One time when I was paying attention (to see if adding more would matter), I noticed lag (I don't normally have lag but at that time got 'very noticeable' lag) when I was around the 600 mark, which went away when I removed some households. I think I decided at the time that I probably shouldn't go over 575 sims.

This doesn't count all my Other households (of added custom townies) but I have trimmed down how many I add. I often go in there and delete the weirdly dressed randoms (who often also have terrible skintones and horrid makeup) that the game spawned.

Thank you so much, that's very helpful to know! I think you're the only person I've seen online to actually mention having the 575+ Sim count and actually document the lag that comes with it. Very useful - now I won't be so hesitant in surpassing the 200 recommended mark.

What grade would you say your computer is in terms of specs, or do you think no matter what kind of system you have, lag will hit past 575 regardless of rig because of game software limits?

It counts all sims, from played, homeless and hidden bin sims.

Another "negative" effect of having too many sims in the world is that it has to generate more and more thumbnails for those sims. With a high end PC, I prefer to have unlimited sims, because I can and do go into the many hundreds of sims over time. But then comes something of a vicious circle which is quite annoying. The file where thumbnail pics are stored, localthumbscache, is only allowed to get to a certain file size where it will then be deleted and rebuilt. Round about the 100 mb file size. With about 600 sims in the world, that thumbnail cache files size is easily reachable, so it could be that every session you load up the game, the thumbnails cache was deleted and has to be rebuilt once again, only to reach max size allowed and be deleted next time you play. I could imagine a paradox incurring that if you had perhaps a thousand sims, the file would become too big before it has fully regenerated all individual sim and family thumbs and have to delete and restart, meaning no more thumbnails ever and the game in an even worse state of lag because it can be highly laggy while thumbnail pics are being rebuilt in the background. Hence the endless annoyance.

To combat this recurring cycle I group many homeless sims into a single family of eight and move them to the hidden sim bin. Where far less thumbs need to be built for the sims, certainly none of the large file size family thumbs that are seen in the played and homeless bins.

So that is one negative effect of allowing unlimited and indeed having large numbers of sims. You gotta start shoving them in the hidden bin to prevent lag! But that will only help you so far, before it just gets too big anyway. I'd be too frightened to go to the 1000 sim mark and the subsequent Purgatory of endless thumbnail generation lag.

I don't recall what my pc's specs are but I bought it a few years ago and my son-in-law was drooling over it. lol


I love having tons of my sims running around in my saves. I made ts4 versions of the ts2 pre-mades (including some extended family that were dead in ts2 (and shared on the gallery)), plus lots of others and those numbers certainly add up. lol

Now coolspear mentions the thumbnails and grouping sims in larger households. While I often delete the localthumbscache myself, I don't pay much attention to thumbnails regenerating (just let them regenerate and then do what I planned to do).

As for grouping sims into larger households, I have found that most sims in larger households will never (or 'very' rarely) be seen in your save and when checked, will not know anyone. I did a little testing and I found I saw more of the sims I added, if they were in single sim (or less then 4) households, if homeless. Households that have homes seemed to be handled a bit differently.
So now, when I add my large households, I split them all up because there is no sense adding a bunch of sims (increasing the sim count), if I will never see them. I can now add less because I am seeing more of them. I also have different saves for different sets of sims so I don't blow up my saves.

This all appears to be true for me, too. I, too, have my maximum set as unlimited. I, too, manually delete my localthumbscache. (Perhaps it's wiser to stop doing this??) I've also noticed the larger the homeless grouping, the less they seem to appear. For example, say, in a bar situation, the game seems to want to generate townies to patronize it than bring the homeless grouped together beyond 4 or 5 for some reason. Never understood that.

Thanks @Coolspear1, I never even thought about the thumbnail cache at all throughout all my digging. I might go delete mine now since it loves to be a bit temperamental - could use a rebuild. Forgive my ignorance, but what is this 'Hidden Sim Bin' you speak of? I didn't know something like this existed.

Also, when you say the 575 counts all Sims in the game, do you mean absolutely ALL Sims? Your own households, randomly generated townies, Maxis NPC's, homeless, etc.?

I may have to find someone to experiment with the 1000+ Sim theory...

@SleepycatDSL You game sounds amazingly fun. I did notice myself that homeless seem to be handled differently, as @dikosay also mentioned. To what end, I'm unsure. Grouping them together into one household sounds like a good idea to prevent oversaturating the thumbnail cache.

I'd really like to do some more digging into this, see just how exactly the game handles exceptional Sim numbers. This is the most information I've had regarding the Sim count since I went surfing the net and multiple sites for information. It's all very messy, shallow, and sometimes conflicting.

The hidden sim bin is where the likes of the Grim Reaper or Alien Pollination Tech NPCs are stored after the game generates them. They are never meant to be seen in the played or homeless bins, the player is never meant to have access to them. Only ever to see Grim Reaper when a sim dies, that's it, that's all.

To access hidden bin a mod will be needed, and MC does provide access. Such that you can move hidden sims out of hidden bin to homeless bin and vice versa. If sim is in hidden bin then the only time a thumbnail image is made of them is if they are known to another sim so there is a thumbnail of them in the Relationship panel. However, using MC to have access to view sims in hidden bin, it does need to generate thumbs of them so you know who's who in the hidden bin. Same thumb types as those you see when travelling and can invite other sims to travel with you to a destination. No family thumbs of sims in hidden bin, so even if there are eight sims, it will only show the single pic of one - whoever it deems as head of that "family." So in the end, far, far less thumbnail images created so less bloating of the cache file overall.

When it comes to players deleting the thumbs cache file regularly, religiously, I have to say that is something I do not practice nor would advise. I put that in the same category a superstition. You may as well touch wood and spin round in a mirror three times, hoping that will fix a game after broken mod. There is nothing in that cache folder other than png thumbnail files. The only time it could help fixing a game problem, is if the creator of a CC clothing or object used the wrong image format in their mod and it breaks the game. Png only, it has to be. But as a cure for fixing your game after broken tuning mods or scripts mods made a mess, that's one leap of illogical faith I'm not going to adopt. So it became an irony to me that my game was always doing it every session because of having 600 plus sims.

Though that was in an older save file I no longer have. My current world does not have as many sims. But I do seem to be getting there slowly but surely. Though this time putting most in hidden bin as they accumulate. And, most assuredly, I do not religiously, superstitiously delete the thumbnail cache. As a modder I've made more mods than I've ever released. Some have been game breaking, hence dropped. Never have I, nor would I , delete an image cache file to clear my game of hiccups no matter what mods I experiment with.

Thanks for clearing that up. I've never thought that cleaning the thumbnail cache would fix broken mods though - ever. I didn't even know that was apparently a common misconception. Think I'll start using that Hidden Sim bin through MCC should my worlds start getting a little clogged, so thanks for shining a light on that.

I actually have over 900 sims in my game. It does cause lag from time to time but that DEPENDS on your game through.

Well I did like performance and I prefer to leave to the game to decide itself of what to cull, But problem is the extended 800 sims limit has been around several years now, and we had numerous new worlds added since, when you have to think of the amount of those that must be, Townies, NPCs and Pets nned to be consider, then it leaves a much smaller pool to fill your worlds, and if you own most of the worlds, then you'll be finding your neglected worlds virtually almost emptying out, more so with the neighborhood stories literaly taking over the game more than the player.