Astroneer is a space sandbox about terraforming and exploring planets with friends. Co-op is where it shines - digging out bases, wiring up power, and shuttling resources across worlds together. But the same question comes up for every group: what happens to the world when the host isn’t online?

This guide covers how Astroneer co-op actually works, where your saves live, and how to share a save so anyone in the group can host the next session.

Does Astroneer Have Dedicated Servers?

Two options exist, and most friend groups end up on the first one:

  • Host-based (P2P) co-op - the default. One player hosts, and up to 4 players total explore together. The catch: the world lives on the host’s machine, and the session only exists while they’re online. When the host logs off, everyone else is grounded.
  • Dedicated servers - Astroneer does support a headless dedicated server (run via SteamCMD), which stays online 24/7 and holds up to 8 players. It solves the availability problem, but it means running a machine around the clock or paying a host - overkill for a handful of friends.

There’s a third path that gets you the always-available world without the server: share the save file itself, so whoever is around can host locally. That’s what this guide focuses on.

Where Is the Astroneer Save File Located?

On the Steam version of Astroneer, saves live in your Windows user folder. Paste this into File Explorer’s address bar (or Win+R):

%LOCALAPPDATA%\Astro\Saved\SaveGames

Each save is an individual file with a .savegame extension - one file per world, not a folder. Astroneer also supports Steam Cloud, so your own saves sync between your devices automatically.

On Game Pass / Microsoft Store? The Xbox PC version stores saves differently, under %LOCALAPPDATA%\Packages\SystemEraSoftworks…\ with obfuscated folder names. If the path above is empty, you’re likely on the Store build.

How Do You Save in Astroneer?

Astroneer autosaves as you play and when you exit - there’s no traditional manual “save game” button. Your progress is written automatically, so quit through the menu rather than force-closing to be sure your latest session is kept. Because saves sync through Steam Cloud, a quick tip: give each world a unique name so identically-named saves don’t collide when moving between machines.

Saving for yourself is easy. The hard part in co-op is getting that .savegame file to whoever wants to host next - which is exactly what SaveSync handles.

How SaveSync Keeps Your Colony Going

SaveSync synchronizes your Astroneer save across every player in the group. When a session ends, the latest save is distributed to everyone automatically. The next time anyone wants to play, they load the current save and host - no waiting on one person, no dedicated server.

How to Set Up SaveSync for Astroneer

  1. Install SaveSync from Steam. Every player needs a copy.
  2. Create a sync group and invite your crew.
  3. Locate the Astroneer save folder (%LOCALAPPDATA%\Astro\Saved\SaveGames, as covered above) and point SaveSync at it.
  4. Play normally. Explore, build, terraform.
  5. SaveSync syncs the save automatically when the session ends.
  6. Anyone can host next time. Load the synced save and keep colonizing.

One-time setup, automatic syncing after that.

Why Use SaveSync Instead of a Dedicated Server

  • No 24/7 machine or hosting bill. A dedicated Astroneer server needs a box running around the clock. SaveSync is a one-time purchase with nothing to keep online.
  • Everyone stays on the latest world. Load an old save and the roads you built, resources you gathered, and bases you wired up in recent sessions vanish. SaveSync guarantees the whole group is on the current save.
  • No manual file passing. Sending .savegame files over Discord before every session breaks the flow. SaveSync does it in the background.
  • Right-sized for friends. Dedicated servers make sense for large persistent communities. For a group of four exploring together, sharing the save is simpler, cheaper, and just works.

Keep Exploring, Whoever’s Online

Astroneer is about the freedom to roam and build across worlds. Your group shouldn’t be stuck waiting on one player’s schedule. With SaveSync, the colony is always reachable - load up, host, and keep pushing out into the system.