Getting Started with Fallout 4 Modding

Fallout 4 modding follows the modern Bethesda stack: a script extender, a mod organiser, a load-order sorter, and a community patch. If you've modded Skyrim Special Edition, this whole flow will feel familiar — the tool names change but the structure is identical.

This guide assumes a fresh Fallout 4 install on PC (Steam). If you're on Xbox, none of this applies — Xbox modding goes through Bethesda.net only and the toolchain is different.

Step 1 — Decide on a game version

Bethesda shipped the Next Gen Update in April 2024, which broke nearly every script-extender-dependent mod overnight. As of 2026, F4SE has caught up but a meaningful fraction of older mods still target the pre-Next-Gen executable.

You have two choices:

Run the current (post-Next-Gen) Fallout 4. Modern F4SE supports it. New mod lists work. Some older mods may not.
Downgrade to the pre-Next-Gen executable. Use the Fallout 4 Downgrader community tool. Locks you into the older F4SE branch but unlocks the larger legacy mod catalogue.

For a first install, go with current Fallout 4. The downgrade path is for users importing a pre-built mod list from before 2024.

Step 2 — Install Mod Organizer 2

Same MO2 install as Skyrim and Oblivion. Create a profile pointing at Fallout 4's install directory.

The principle holds: don't install mods directly into Fallout 4's folder. MO2's virtual file system manages everything.

Step 3 — Install F4SE

Fallout 4 Script Extender (F4SE) for your game version. Extract to your Fallout 4 install directory:

f4se_loader.exe
f4se_*.dll
Data/Scripts/ folder
Data/F4SE/Plugins/ folder

In MO2, add F4SE as an executable and launch through it. The main menu's bottom-left should show the F4SE version.

Step 4 — Install Buffout 4

Buffout 4 is an F4SE plugin that improves crash logging and patches engine bugs. It is mandatory for any modded Fallout 4 install — vanilla Fallout 4 has known threading bugs that crash randomly under mod load.

Install through MO2. Buffout 4 places its DLL in Data/F4SE/Plugins/ and loads automatically.

Step 5 — Install the essentials

Unofficial Fallout 4 Patch (UFO4P) — community bug fixes.
Address Library for F4SE Plugins — compatibility shim most F4SE plugins depend on.
High FPS Physics Fix — patches frame-rate-dependent physics issues. Important on modern displays above 60Hz.

Install through MO2. Load UFO4P near the top of the plugin list (right after the DLC ESMs).

Step 6 — Run LOOT

Sort, apply, done. LOOT's auto-sort handles 95%+ of Fallout 4 plugin ordering needs.

Step 7 — Start a new save

Same discipline as Skyrim: don't add or remove script-injecting mods mid-playthrough. Settlement system mods are particularly sticky — removing one mid-save leaves orphaned workshop objects forever.

Common gotchas

F4SE version mismatch. F4SE builds are tied to specific Fallout 4 executable versions. After any game update, check F4SE for the matching build.
"This file is unrecognised by F4SE". F4SE plugins (the F4SE DLLs in Data/F4SE/Plugins/) are also version-locked. The Address Library helps but doesn't fully eliminate the issue. Update plugins when you update F4SE.
Game crashes randomly without Buffout 4. This isn't a mod problem, it's a vanilla Fallout 4 problem. Install Buffout 4.
Settlement objects appear/disappear. Almost always a mod load-order issue. Run LOOT, then xEdit to check for conflicts on workshop records.
The "Next Gen Update" broke my mods. Either downgrade or wait for the mod author to update. Most popular mods are updated post-NGU, but some smaller ones may have been abandoned.

If you're new to Bethesda modding generally, Skyrim Special Edition has a slightly easier learning curve. But Fallout 4's settlement system makes it uniquely modder-friendly for base-building content — there's no equivalent in Skyrim.