Zombie Respawn Woes? Lock the Undead Out in PZ
Tired of clearing the same zombies over and over? You're not alone. In Project Zomboid, the default settings make zombies reappear ("respawn") a few days after you kill them. Fortunately, you can turn this off. This guide (for Builds 41 and 42) will quickly show you how to disable zombie respawns โ whether you're playing solo or running a server โ so once a zombie is dead, it stays dead. For more detailed respawn mechanics, see our comprehensive respawn guide.
Quick Start: No-Respawn in 30 Seconds
If you just want the quick steps to stop zombies from respawning, here you go:
- Start a Custom Sandbox game. From the main menu, select Solo โ Custom Sandbox (or configure your server's sandbox settings). For server management, check our admin guide.
- Open Advanced Zombie Options. After choosing a spawn location, click the Advanced Zombie Options tab.
- Set "Respawn Hours" to "0". This tells the game that zero hours need to pass for a respawn โ effectively disabling it. (You can also set Respawn Unseen Hours to 0; if Respawn is off, this value is ignored.)
- [Optional] Turn off migration. Set Redistribute Hours to 0 as well if you don't want zombies migrating into cleared areas.
- Start your game. Enjoy a world where once you clear a town, it stays clear (mostly โ see Zombie Migration below).
Already have a server running? As the admin, open the Admin Panel (bottom-right icon) โ Sandbox Options, and adjust the settings there, just like above, then hit Apply. Restart the server to apply changes.
That's the gist! Below we'll dive into full details, including Build 42 quirks, config files, mods for mid-game changes, and what to expect in a no-respawn apocalypse.
Zombies Keep Coming Back! Why Respawn Exists (and How B42 Changed It)
Before flipping the "off" switch, it helps to know what we're turning off. Project Zomboid uses a respawn system to repopulate areas with zombies over time. In Build 41, by default 10% of a cell's zombie population will respawn every 72 hours. In other words, if you clear a neighborhood of 100 zombies, about 10 will "magically" reappear after three in-game days (assuming you haven't been around). Build 42, however, introduced new dynamics that made respawns (and migration) feel harsher โ many players noticed far more zombies, even in supposedly cleared spots.
Default Respawn Mechanics (B41)
Under the hood, the game divides the map into "cells" (~300x300 tiles each). By default, if a cell isn't visited for a while, a fraction of its zombies will respawn. Specifically:
- Respawn Hours = 72 (3 days)
- Respawn Multiplier = 0.1 (10%)
- Respawn Unseen Hours = 16
The clock starts once you leave; ~3 days later, some zombies respawn on the cell edges. If you keep living in an area, respawns shouldn't trigger there because the cell isn't "unseen" for long enough.
Build 42's Twist
Build 42 (unstable as of late 2024) shook things up. The devs implemented a "zombie distribution heatmap" system and other AI changes that effectively made zombies flow into cleared areas much faster and in greater numbers.
Key changes:
- Increased default Rally Group size (from 20 to 50)
- More aggressive migration to fill cleared areas
- Initial spawn bug that maxed out population
Early B42 builds launched with a glitch: if you tried to change zombie spawn settings in sandbox (like lowering the population or respawn), the game would instead max out the zombie count in the world. A temporary workaround was to leave settings at default, start the game, then use a mod to adjust. By Build 42.6 they fixed several spawn issues and outright removed wilderness spawning.
Bottom line: Build 41's respawn can be tamed via settings, and Build 42 aims for a tougher world (with roaming hordes and initially bugged settings). But in both cases, if you want a truly cleared world, you can disable respawns entirely. Next, we'll dive into exactly how to do that for your game mode of choice.
Single-Player: Making Sure Zombies Stay Dead
If you're playing solo, the game gives you full control over zombie settings when you start a new world. The key is the Custom Sandbox settings. Here's how to set up a single-player game with no zombie respawn:
New Game Setup โ Disable Respawn via Sandbox Options
When starting a new world in Build 41 or 42, follow these steps:
- Select "Custom Sandbox". From the main menu, click Solo, pick any spawn location you like (this can be changed later), then choose Custom Sandbox as the playstyle. This opens the sandbox settings UI with a bunch of tabs.
- Go to Advanced Zombie Options. Click through the tabs on the left until you see Advanced Zombie Options (it's the last tab, after all the loot and world settings).
- Set "Respawn Hours" to 0. Find the setting labeled "Respawn Hours" (default is 72 hours). Change that value to 0. This tells the game that zero hours must pass before zombies respawn, which effectively means no respawn at all.
- Set "Respawn Unseen Hours" to 0 (optional). Normally, "Respawn Unseen Hours" is the time a cell must remain unseen for respawns to occur (default 16). If respawn is off, this setting doesn't really matter. But to be safe, you can set it to 0 as well, or just leave it โ with Respawn Hours at 0, no respawns will happen regardless.
- [Optional] Set "Respawn Multiplier" to 0.0. This is the percentage of zombies that respawn each cycle (default 0.1 or 10%). If Respawn Hours = 0, the multiplier is moot (there's no "cycle" to run). However, some players set it to 0.0 for peace of mind or in case they later re-enable respawn.
- [Optional] Set "Redistribute Hours" to 0. This one is important if you want no new zombies, period. Redistribute Hours (aka Zombie Migration) is how often zombies move to fill empty areas in the same cell. Default is 12. If you leave this on, then even though no new zombies spawn, any zombies from neighboring parts of the cell will eventually wander into the cleared part after X hours. Setting Redistribute Hours = 0 turns off this migration mechanic, meaning zombies won't automatically shift around.
- Double-check other settings as desired (you might also disable the helicopter event if you truly want a calm experience, since the chopper can drag hordes from afar). Then start the game!
Even with respawn off, if your Population Peak Day is in the future (default Day 28) and your Peak Multiplier is higher than your Start Multiplier, the game will continue spawning new zombies each day until it reaches the peak. If you truly want no new zombies at all after day one, make sure to set Population Start Multiplier = Population Peak Multiplier (and you can set Peak Day to 1).
TL;DR: For new games, the critical setting is Respawn Hours = 0 (that alone turns off respawns completely). Adjust the other values (Unseen, Multiplier, Redistribute) to taste, and watch out for the population peak settings.
Disabling Respawn in an Ongoing Save
Maybe you started on default settings and a week in, you're fed up with the endless zeds creeping back into your safehouse. Do you have to start a new world to disable respawns? No! There are ways to change sandbox settings mid-game โ though it's a bit trickier in single-player than multiplayer.
Multiplayer: No-Respawn Settings for Servers
Running a server or a co-op game with friends? You can also disable zombie respawns in multiplayer. The process is similar โ it involves changing the sandbox options either before world launch or on the fly with admin privileges.
Hosted Server (Co-op) โ Setting No Respawn
If you're using the in-game Host option to play with friends, you have access to the same sandbox customization as single-player:
- After clicking Host, you can set up a server settings preset.
- Go through the sandbox options and under Advanced Zombie Options, set Respawn Hours = 0 just like in single-player.
- Save the preset and launch the server. All clients who join will now be in a no-respawn world.
- On the main menu, hit Host, select your server settings file, and click Edit Settings.
- Navigate to Advanced Zombie Options and adjust the respawn values (Hours to 0, etc.).
- Save, then start the server.
One thing to remember on hosted servers: if you change settings while the server is running, they may not take effect until a restart. Best practice is to shut down the server, edit the settings, then restart so it cleanly loads the new sandbox vars.
Dedicated Server โ Config Files Method
For dedicated servers (when you run the Project Zomboid server separately, e.g., on a VPS or your spare PC), you'll be editing configuration files directly or via a control panel provided by your host.
In the server's installation directory (or Zomboid/Server folder on Windows), find the file named <ServerName>_SandboxVars.lua (by default, servertest_SandboxVars.lua if your server is "servertest"). Open this file in a text editor.
Similar to single-player, you'll see a Lua table of sandbox settings. Edit the values:
RespawnHours = 0,
RespawnUnseenHours = 0,
RespawnMultiplier = 0.0,
RedistributeHours = 0,
Ensure commas and syntax are correct. Setting RespawnHours = 0 is the key to disable respawn.
It's crucial to restart because the server reads those files on startup. If the server was running while you edited, it won't magically update live. Always do a controlled shutdown and restart. In a console you can use the quit command to gracefully save and stop the server. Wait for it to fully stop, then start it up again.
Admin In-Game Method
If you have a dedicated server running and want to change respawn settings without editing files manually, you can do it as an admin while in-game:
If you're the server owner, you likely already have an admin account or password. If not, you can make your player an admin by typing in the server console: setaccesslevel "YourUsername" admin. Or if you have admin password, log in using /admin <password> in chat.
In-game, as admin, you'll see a small admin icon (a red button that says "Admin" or a skull icon in newer builds) on the UI. Click it and choose Sandbox Options.
Go to Advanced Zombie Options, set Respawn Hours to 0 (and others as needed).
Click the Apply or Save button in that panel. The server will broadcast that sandbox settings have been changed. For best results, restart the server after changing to ensure all settings take effect properly.
In multiplayer, you can verify the new setting by typing /showoptions in the chat (if cheats are enabled) or simply observing the behavior over a few in-game days. With respawn off, areas cleared by players should remain at the reduced zombie count indefinitely.
Advanced Tweaks & Troubleshooting
Disabling respawn will definitely thin out the undead over time โ eventually, the world's population can only go down as you clear them. However, players are sometimes surprised to still see zombies wandering into cleared zones, or they wonder if the game is truly respecting the settings. Let's address a few common points:
Zombie Migration vs. Respawn
What is Zombie Migration?
Even with Respawn off, zombies can move between areas. The game has a mechanic often called "migration" or redistribution. By default, every 12 hours, zombies that are in a densely populated part of a cell may drift toward less populated parts. This is controlled by the Redistribute Hours sandbox setting.
Solution: Disable Migration
If you truly want an area to remain empty after clearing, set Redistribute Hours = 0. This effectively stops the automatic migration algorithm. Zombies will still move around if attracted by sound (a gunshot can still draw zombies from far away) or if they were already on the move, but they won't systematically fill up empty cells just because the cell is empty.
Example scenario: You cleared a parking lot, but the next day a bunch of zombies from the next street have wandered over to that parking lot. They didn't respawn out of thin air โ they walked there.
Some players choose a middle ground: keep some migration but no respawn. For example, you might leave Redistribute on but high (say 72 hours) so that occasionally zombies might drift in, but not constantly. This mimics the idea that zombies can roam, but you won't get immediate backfill.
"I turned respawn off, why do I see new zombies?"
Aside from migration, there are a few reasons you might still see zombies after clearing an area:
Project Zomboid doesn't spawn every zombie in the world at once. It spawns them as you explore new areas for the first time. So, if you clear your town and then drive 2 blocks over into a place you've never been, you will encounter zombies โ not because they respawned, but because the game is spawning that cell's zombies for the first time as you go there.
The helicopter event (if enabled) can drag hordes from far away. If you're holed up and suddenly a big group shows up despite no respawn, likely the helicopter or a gunshot event off-screen moved them. Fire alarms, distant screams, thunder โ these can all cause some movement.
As discussed, if it hasn't reached Peak Day yet, the game might still be adding zombies to meet the target peak population. Once past peak day (or if peak pop == start pop), this won't happen.
If you're on a server and still see obvious respawning, double-check the server settings. Sometimes server admins forget to edit both the ini and SandboxVars, or a typo in the config means the server fell back to default.
Build 42 Quirks and Fixes
By now, Build 42's unstable branch has seen some fixes. They removed "wilderness spawns" by default in one patch, meaning forests won't keep spawning zombies on top of initial ones. Early on, people reported remote cabins getting swarmed which shouldn't happen as much now with that change. If you're playing B42 and trying to disable respawn:
The Indie Stone is actively patching B42 unstable. Check the official forum's build notes โ if a note appears like "Fixed sandbox spawn settings not applying," then you'll know the glitch is solved.
Living in a World With No Respawns: What to Expect
So you've done it โ you turned off zombie respawns. How does the gameplay change?
Early Game
In the first days and weeks, you won't notice a huge difference except perhaps slightly fewer stragglers behind you. There's still a hefty initial population to contend with. You need to be just as careful and resourceful clearing out your base area. But you can make steady progress in thinning out local zombies without the usual concern that they'll be back tomorrow.
Mid Game (Cleared Zones)
As time goes on, you'll start seeing the effects. Perhaps you focus on one town or neighborhood โ after systematically destroying all zombies there, that area becomes relatively safe. You might walk down Main Street and find it eerily empty, with only flies buzzing over corpses. This can almost make the game feel like a different mode โ it shifts from constant combat to an eerie post-apocalypse scavenging and base-building vibe.
Late Game (Horde Hunts)
Eventually, you might find yourself actively seeking out remaining pockets of zombies because your immediate surroundings have none. The challenge becomes more about travel (you might have to go to another town to find danger or loot) and sustainability. It can become a story of reclamation: maybe you clear town after town, doing a "sweep" of the map.
The biggest threat in a no-respawn game is thinking an area is 100% safe when maybe a few unseen zombies were still around or wandered in. Complacency can still get you killed โ all it takes is one surprise shambler in your supposedly secure base to bite you while you're organizing loot.
Resources & Loot
One indirect effect โ with zombie numbers only decreasing, you have a finite amount of loot accessible from zombie corpses (if you care about things like beta blockers, watches, etc., from zombies). And if you also turn off loot respawn (common to do for realism), the world's supplies are limited too.
This can actually increase the late-game challenge in a different way: you might run out of certain supplies and have to travel farther into uncleared territory to get them. It's a trade-off: no respawning enemies, but also no "free" replenishment of loot. Eventually, the game can shift from combat focus to pure survival (farming, crafting, hunting) because you've eliminated most threats.
Multiplayer Dynamics
On a server, disabling respawn can create a very different vibe. The community could work together to clear a town and actually succeed in making a safe settlement. It can be really cool for RP (roleplay) servers โ imagine a safe zone that's genuinely safe because the players cleared it.
But it also means if new players join late, they may have to travel far to find zombies to fight (or the server could manually trigger events to spawn some challenges). With no respawn, PvE servers will eventually run out of zombies, so sometimes admins schedule soft resets or encourage moving to new regions of the map as "seasons."
In summary
Turning off zombie respawn in Project Zomboid fundamentally changes the gameplay loop โ it shifts from a war of attrition (where zombies always come back) to a war of conquest (where you can methodically take back territory). There's no right or wrong way โ it's your apocalypse!
Now go forth and enjoy your (hopefully) zombie-free safehouse. Just remember: even if the zombies aren't coming back, keep your guard up, survivor. Complacency kills as surely as a zombie bite. Good luck, and have fun tailoring the apocalypse to your liking!
I once tried a no-respawn run in West Point โ after weeks of bloody work, I actually cleared the entire downtown. It was surreal walking those streets with every shop door wide open, knowing I'd personally "evicted" all the former tenants. It felt greatโฆ until a helicopter dragged about two hundred zombies from the outskirts straight into my peaceful town square barbeque. I learned two things: 1) Always be ready for wandering hordes, even in a no-respawn game, and 2) never grill indoors (half my base burned down in that barbeque ๐). So, plan accordingly and enjoy the unique challenges of a finite-zombie world!