Where tModLoader stands on 1.4.5
Vanilla Terraria on PC is on 1.4.5.8. tModLoader, the modding port, is not: its own guide for players states it plainly — "Currently the stable version is based on Terraria v1.4.4 content", with the stable branch "currently based on Terraria 1.4.4.9 content". The releases page agrees as of today: the newest stable release, v2026.07.3.0 (September 1, 2026), and the newest preview, v2026.08.2.2 (September 23, 2026), both come from the 1.4.4 branch. A tModLoader server today is a 1.4.4-series server, not a 1.4.5.8 one.
When does that change? The maintainers' information issue for the port, tModLoader issue #5070, is still open, and its wording has not moved since it was posted on March 31, 2026: "Updating tModLoader to 1.4.5 is a large undertaking and will take many months yet." Progress is real but early — the same issue says the 1.4.5 branch "is currently buildable and launches, but there is much work to be done" — and there is a contributor-facing Steam branch, 1.4.5-dev, that updates per commit. None of that is a player release. Until a stable 1.4.5 tModLoader ships, "months away" is the honest planning assumption for a modded world.
Two consequences worth writing down. First, 1.4.4 is not being abandoned when 1.4.5 arrives: issue #5070 says it "will be supported as a Legacy version like 1.3 and 1.4.3", both of which still have legacy releases on the downloads page today. Second, mods will not all cross the gap at once — asked whether mods will be updated for 1.4.5, the issue answers: "Due to how much has changed in the Terraria v1.4.5 update, the short answer to this is 'no'", with maintained mods expected to be ready around the stable release. If you are starting a modded world now, you are starting it on 1.4.4-series tModLoader either way.
What that means for who can join
A modded server takes only clients that match it. A vanilla Terraria 1.4.5.8 client cannot join a tModLoader server, and a tModLoader client cannot join a vanilla 1.4.5.8 server — the version check at the door is the same one behind the classic "not using the same version" refusal, which our Terraria server not connecting guide covers. Everyone on a modded server also needs the same enabled mods, not just the same program version. Steam players pick the same branch (the stable default, or a preview) on every machine; the branch list and what each is for is in the guide for players.
A second program, not an add-on
Modded Terraria is not a switch on the vanilla server; it is a separate install of a separate program. The players' guide is explicit that "The tModLoader installation will exist alongside the vanilla installation", and just as explicit about the mistake to avoid: "DO NOT install the tModLoader files directly into the Terraria folder." You get it from Steam, from GitHub, or through either of the server-install routes below — and the project notes the GitHub release is "the same version as released on Steam".
One platform warning from the project's own dedicated-server readme: "Currently ARM support does not exist for TML or the Dedicated Server" — if you are picking a machine to self-host on, that rules out the common ARM boards and the cheapest ARM cloud instances today.
The start scripts
tModLoader ships its own server launchers, and they are the supported way to start the program by hand: start-tModLoaderServer.bat on Windows and start-tModLoaderServer.sh on Linux and macOS, both listed in the project's Starting a modded server wiki page. That page carries a banner worth taking seriously — "This page is outdated for 1.4.4 dedicated servers" — and points at the dedicated-server utilities readme linked below for current detail, but the scripts and the flags it documents are the ones the release still carries.
The flags are the vanilla server's own, and our serverconfig.txt reference covers them key by key. The ones a modded server actually leans on: -config serverconfig.txt to run from a config file (the readme's example sets world to the exact path of a world, worldname for a world autocreate will make, and autocreate=1 so one is created if none exists there), -world pointing at a .wld file — the wiki page stresses it must be the .wld, not the .twld — and -nosteam for a server that does not use Steam's matchmaking. The wiki also suggests running the script under screen or tmux on a headless Linux box, which is ordinary practice for any dedicated server.
SteamCMD, GitHub and the management script
The current, readme-recommended way to stand a modded server up on Linux is the folder layout plus one management script, documented in the Dedicated Server Utils readme on the 1.4.4 branch. The layout it requires is one folder holding Mods/ (your .tmod files, install.txt and enabled.json), Worlds/, an optional serverconfig.txt, and the script itself: manage-tModLoaderServer.sh.
The script wraps both install sources. The SteamCMD route — the readme's recommended one — needs SteamCMD installed and on your PATH, then runs ./manage-tModLoaderServer.sh install-tml --username your_steam_username, prompting for password and any two-factor code, and installs into a server folder beside your layout. Under the hood it is SteamCMD's ordinary invocation, fetching tModLoader's app id 1281930 with +app_update using your login (workshop items, fetched separately by install-mods, download anonymously). The GitHub route is ./manage-tModLoaderServer.sh install-tml --github, which pulls the latest release — "the same version as released on Steam" — and can be pinned to a specific version with a tmlversion.txt or the TMLVERSION environment variable when a modpack demands an older one. Mods go on with install-mods, the server starts with start, and re-running install updates both the program and the mods. The readme also documents a Docker route it recommends first if you would rather hold the whole thing in a container.
install.txt and enabled.json
Two small files decide what a modded server loads, and the readme is exact about both. install.txt lists the mods to fetch from the Steam Workshop, and enabled.json lists the mods that load when the server starts — "install.txt and enabled.json are needed for any mods you wish to install from the Steam Workshop", because "The steam workshop does not use mod names to identify mods, so a modpack should be made to install mods from the workshop". Their absence is not a small mistake: "No mods will be installed if install.txt is missing, and no mods will be enabled if enabled.json is missing. You will need a Mods/enabled.json to contain all Mods that you want enabled, including local mods."
The project's way to produce the pair is from the game itself: on the tModLoader main menu, open Workshop, then Mod Packs, click "Save Enabled as New Mod Pack", then "Open Mod Pack Folder", and copy the install.txt and enabled.json out of your modpack's folder into the server's Mods folder. Mods you write or download by hand as .tmod files just sit in that same Mods folder, and enabled.json is what turns them on. This is the same pair of files our Terraria server requirements guide points at when it explains why a modded server's footprint is the mod list's, not the vanilla server's.
Calamity and other large mods
The question "can I play Calamity on 1.4.5" has one honest answer today: not on a 1.4.5 server. The Calamity Mod's own wiki describes it as "a large content mod for Terraria", and its supported-versions table currently lists Terraria 1.4.4.9 with a matching tModLoader release and no 1.4.5 entry. Calamity runs on tModLoader, tModLoader's stable is built on 1.4.4 content, so a Calamity world is a 1.4.4-series world joined through tModLoader by everyone on it. The same holds for any other large content mod: check the mod's own page for the tModLoader version it targets before planning a server around it.
Renting, and where mod questions go
This page is the how-to, not a product claim: nothing here says any particular host runs tModLoader for you, and a modded server's moving parts — the version gap, the mod list, the two files — are yours to keep straight on any machine you rent or own. Questions about a specific mod are best asked where that mod is maintained, and tModLoader's own wiki and issue tracker are the primary sources linked throughout this page. If you have a question about what a ForgeWorld Gaming plan runs, support answers those at support@fwg.world.
If you would rather have a server that stays online without running it yourself, ForgeWorld Gaming’s Terraria plan is Terraria Standard, 4 player slots, CA$8.99/month; the availability page shows whether orders are currently open. Other sizes and tiers are not available yet. Your server is set up automatically after payment. Current plans and prices are on the Terraria availability page.