SCP: Secret LaboratoryHow to Whitelist an SCP Secret Laboratory Server (and Reserved Slots)
Whitelist an SCP:SL server: set enable_whitelist to true in config_gameplay.txt, add SteamID64@steam lines to UserIDWhitelist.txt, and set up reserved slots.
Updated Oct 7, 2026 · 4 min read
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To whitelist an SCP: Secret Laboratory server, open config_gameplay.txt in your server's port folder, change enable_whitelist from false to true, then list allowed players in UserIDWhitelist.txt in the same folder, one per line as 76561198000000000@steam (or @discord for Discord accounts). Restart the server and only listed players can join. Reserved slots work the same way with UserIDReservedSlots.txt: listed players can join even when the public slots are full.
Northwood's own tech wiki documents the whitelist steps. The two details people miss are the port named config folder and the @steam suffix on every ID.
Step 1: Find the right config folder
SCP:SL keeps a separate set of config files for each port the server runs on. The folder is named after the port, usually 7777:
| System | Folder |
|---|---|
| Windows | %AppData%\SCP Secret Laboratory\config\7777\ |
| Linux | ~/.config/SCP Secret Laboratory/config/7777/ |
If you run more than one server, each has its own folder. Editing the 7777 folder does nothing for a server on port 7778. This is the most common reason a whitelist "does not work".
Step 2: Turn the whitelist on
Open config_gameplay.txt in that folder and find:
enable_whitelist: false
Change it to:
enable_whitelist: true
Keep the YAML style formatting exactly as it is: the key, a colon, a space, then the value. Do not add tabs.
Step 3: Add players to UserIDWhitelist.txt
In the same folder, open UserIDWhitelist.txt. Each line holds one user ID with its platform suffix. Lines starting with # are comments:
#Put one UserID per line. Lines prefixed with "#" are ignored.
# Staff
76561198000000001@steam
76561198000000002@steam
# Discord linked member
274613382353518592@discord
To find a SteamID64, paste the player's Steam profile link into a SteamID lookup site such as steamid.io. It is the 17 digit number starting with 7656. Then add @steam. A bare number without the suffix will not match.
Save, then restart the server. Players not on the list are refused when they try to join.
Reserved slots
Reserved slots are the softer option. The server stays public, but a few seats are held for people you choose, so your regulars and staff can get in when it is full.
- Open
UserIDReservedSlots.txtin the same config folder. - Add one user ID per line, in the same
SteamID64@steamformat. - Check
config_gameplay.txtfor the reserved slot settings (search forreserved) and make sure reserved slots are turned on. - Restart the server.
Players on the list can then fill the reserved seats even when the public counter shows the server as full. It is a good reward for long time players and keeps staff able to join during peak hours.
Whitelist, reserved slots or a password?
| Option | Best for | Downside |
|---|---|---|
| Whitelist | Private communities, events, closed testing | You maintain a list of IDs |
| Reserved slots | Public servers that fill up | Does not keep anyone out |
| No list, just Direct Connect | Small friend groups | Anyone with the address can join |
For a staff only test server, a whitelist is cleaner than sharing the address and hoping it does not spread.
Keeping the list manageable
- Comment as you go. A
#line with a name above each ID saves you from guessing who76561198...is six months later. - Use Remote Admin ranks for staff. The whitelist only decides who can join. What they can do in game is set by ranks in
config_remoteadmin.txt, in the same folder. - Back up the folder. The whole
config/<port>folder is your server's identity: gameplay settings, ranks, whitelist and reserved slots. Copy it before big changes and before game updates.
Common problems
| Problem | Fix |
|---|---|
| Whitelisted player still refused | Missing @steam suffix, or a typo in the 17 digits |
| Whitelist ignored entirely | Edited the wrong port folder, or did not restart |
| Server will not start after editing | A formatting error in config_gameplay.txt, such as a tab or missing space |
| Everyone can still join | enable_whitelist is still false |
| Reserved slot does nothing | Reserved slots are off in the config, or the server is not actually full |
Doing it on a hosted server
On a GamezServers SCP: Secret Laboratory server, the config folder named after your server's port is in the file manager, along with config_gameplay.txt, UserIDWhitelist.txt, UserIDReservedSlots.txt and config_remoteadmin.txt. Edit, save, restart from the panel, and test with a friend. One click backups cover the folder before big changes. The server type (Standard or EXILED) is a panel setting, and our EXILED plugin guide covers plugins that add their own whitelist and slot tools. For the rest of the setup, see our SCP:SL hosting guide.
FAQ
Where is UserIDWhitelist.txt on an SCP:SL server?
In the config folder named after your server's port, such as config/7777, next to config_gameplay.txt.
What format do SCP:SL whitelist entries use?
One ID per line with its platform suffix, such as 76561198000000000@steam or 274613382353518592@discord.
How do I turn on the whitelist?
Set enable_whitelist: true in config_gameplay.txt and restart the server.
What is the difference between a whitelist and reserved slots?
A whitelist blocks everyone not on the list. Reserved slots keep the server public but hold seats for listed players when it is full.
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