Online co-op RTS games

Every online co-op RTS game on Steam we know of, newest first. Add tags or a price band to narrow it down.

Showing 1–10 of 213 games matching RTS Β· updated 12 Oct 2026

Filters: RTS Γ— Clear all
$
Released
Price
$ Β· Cheap
Players
πŸ‘₯ Not stated

Build your own spaceship tile by tile, wire every system by hand and keep the oxygen flowing. A hardcore top-down survival builder where one bad cable can end your journey. Fly solo or team up with friends – each captain in their own ship.

$$
Released
Price
$$ Β· Standard
Players
πŸ‘₯ Not stated
Reviews
0% of 4

Command armor, infantry, artillery, aircraft, drones and naval forces in a modern real-time wargame. Build your army, scout enemy positions and capture objectives. Play solo against AI or online with other commanders, with eight nations and distinct equipment rosters.

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Free
Released
Price
Free
Players
πŸ‘₯ Not stated
Reviews
72% of 50

FrontWars is a free-to-play multiplayer strategy game where hundreds of players battle for global domination! Build alliances, command armies, grow your economy, and unleash nuclear strikes to wipe your rivals off the map. No pay-to-win: only the strongest will rule the world.

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$
Released
Price
$ Β· Cheap
Players
πŸ‘₯ Not stated
Reviews
100% of 3

You command Ukraine's air defense. Every night β€” missiles and drone swarms, and always fewer interceptors than targets. By day it's your turn: deep strikes past enemy radars. And when orders aren't enough β€” take the stick yourself.

Free
Released
Price
Free
Players
πŸ‘₯ Up to 8 players
Reviews
60% of 5

Build a planetary empire, research game-changing tech, and raid real players across a persistent galaxy. The classic browser space strategy, reborn - and finally fair: no pay-to-win, ever. Team up for 8-fleet combined attacks. Your mines keep working while you sleep.

$$
Released
Price
$$ Β· Standard
Players
πŸ‘₯ Up to 16 players
Reviews
100% of 1

Build an island empire, automate sprawling production chains, and compete with up to 16 players across a procedurally generated ocean.

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$$
Released
Price
$$ Β· Standard
Players
πŸ‘₯ Up to 3 players
Reviews
86% of 82

Hold the line or everything falls. Wavecrashers is a 3-player co-op strategy game where heroes defend against relentless waves of enemies. Build powerful synergies, push your limits, and survive the chaos. Play solo with bots or team up with friends. Every run is a fight to endure the storm.

$
Released
Price
$ Β· Cheap
Players
πŸ‘₯ Not stated
Reviews
72% of 25

"Girls vs Zombies": Multiplayer cooperative 3D tower defense. Grab your gun and fight with friends against Eastern and Western demons, or oversee and deploy beautiful girls, defending against zombie waves with swords, guns, and magic!

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Free
Released
Price
Free
Players
πŸ‘₯ Not stated
Reviews
25% of 4

A multiplayer turn-based survival strategy game where you vote, deceive, use action cards, and survive relentless zombie attacks to escape alive.

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