Removing a mod is simpler than adding one, but a world that already has that mod's blocks, items, or entities placed in it needs a bit more care than just deleting a jar file.
Back up first
As with any change to a modded server, back up your world folder and mods folder before removing anything. If the mod turns out to be load-bearing in a way you did not expect, this is your way back.
Step 1: Check what the mod actually added to your world
If the mod added blocks, items, or entities that players have already placed or collected, removing it outright can leave "missing registry" errors, floating unknown blocks, or a world that refuses to load certain chunks entirely. This matters far more for content-heavy mods (new blocks and machines) than for purely mechanical or utility mods that do not touch world data.
Step 2: Check for dependent mods
Before removing a shared library like Fabric API, Cloth Config, or Architectury API, confirm no other installed mod still needs it, removing a dependency out from under a mod that relies on it will crash the server on the next start. The dependency list on each mod's Modrinth or CurseForge page tells you what needs what.
Step 3: Remove the jar
Stop the server, delete the mod's .jar file from the mods folder, and remove its configuration folder under config/ if you want a completely clean removal (leaving it does no harm, it just sits unused).
Step 4: Restart and check the log
Start the server and watch logs/latest.log. A clean start with no errors mentioning the removed mod's name (or a mod that depended on it) means the removal went smoothly.
If chunks won't load after removal
This almost always means the mod's blocks or entities are still physically present somewhere in the world. Restoring from your backup and instead disabling the mod's specific content through its configuration (if it offers that option) is usually safer than a hard removal once a mod is genuinely embedded in your world.
Removing it from clients too
If the mod was client-visible (most gameplay mods are), every player needs to remove it from their own mods folder as well, or they may be rejected when connecting to a server that no longer expects it.
Keeping mod management simple
Tick Hosting's file manager lets you delete mod jars and config folders directly from the dashboard, with one-click backups first, so testing a removal is low-risk. Available on every plan, including the free tier, from Tick Hosting's plans page.