Free Online Co-Op Games on Steam
Steam currently has 8,668 Online Co-Op games available to download and play. Explore our list of the best free games ranked by popularity and ratings. Data for this list is calculated from reviews and player counts reported directly by Steam and will be updated in real-time. Free Online Co-Op game rankings were last updated on 2/13/2026.
Looking for more? Explore other lists such as:
- Best online co-op games on Steam
- Best online co-op Steam Deck games
- Best online co-op Steam games for Mac OS
- Best online co-op Linux games on Steam
- Free Steam games
- Most played Steam games
- Best rated Steam games
1. Counter-Strike 2
For over two decades, Counter-Strike has offered an elite competitive experience, one shaped by millions of players from across the globe. And now the next chapter in the CS story is about to begin. This is Counter-Strike 2.
Counter-Strike 2 holds the #1 spot for "best free Online Co-Op game on Steam" with a Player Score of 86. Its score was calculated by analyzing a total of 9,383,520 reviews on Steam. This breaks down to a total of 8,100,165 positive reviews and 1,283,355 negative reviews — making it "Very Positive" on Steam.
It can be played and ran on both Windows and Linux systems. At the moment, it is possible to play Counter-Strike 2 on the Steam Deck (though some functionality may be limited).
2. Dota 2
Every day, millions of players worldwide enter battle as one of over a hundred Dota heroes. And no matter if it's their 10th hour of play or 1,000th, there's always something new to discover. With regular updates that ensure a constant evolution of gameplay, features, and heroes, Dota 2 has taken on a life of its own.
Dota 2 has achieved a Player Score of 81, placing it in the #2 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 2,664,663 reviews on Steam. This breaks down to a total of 2,163,214 positive reviews and 501,449 negative reviews — making it "Very Positive" on Steam.
It can be played and ran on Windows, Mac, and Linux systems. At the moment, it is possible to play Dota 2 on the Steam Deck (though some functionality may be limited).
3. Marvel Rivals
Marvel Rivals is a Super Hero Team-Based PVP Shooter! Assemble an all-star Marvel squad, devise countless strategies by combining powers to form unique Team-Up skills and fight in destructible, ever-changing battlefields across the continually evolving Marvel universe!
Marvel Rivals has achieved a Player Score of 77, placing it in the #3 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 367,932 reviews on Steam. This breaks down to a total of 284,600 positive reviews and 83,332 negative reviews — making it "Mostly Positive" on Steam.
It can be played and ran on Windows systems. At the moment, it is possible to play Marvel Rivals on the Steam Deck (though some functionality may be limited).
| Release Date | 12/6/2024 |
| Developer | NetEase Games |
| Publisher | NetEase Games |
| Steam App Id | 2767030 |
4. PUBG: BATTLEGROUNDS
PUBG: BATTLEGROUNDS, the high-stakes winner-take-all shooter that started the Battle Royale craze, is free-to-play! Drop into diverse maps, loot unique weapons and supplies, and survive in an ever-shrinking zone where every turn could be your last.
PUBG: BATTLEGROUNDS has achieved a Player Score of 60, placing it in the #4 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 2,672,929 reviews on Steam. This breaks down to a total of 1,605,716 positive reviews and 1,067,213 negative reviews — making it "Mixed" on Steam.
It can be played and ran on Windows systems. At the moment, it is not possible to play or run PUBG: BATTLEGROUNDS on the Steam Deck.
| Release Date | 12/21/2017 |
| Franchise | KRAFTON, Inc. |
| Developers | |
| Publisher | KRAFTON, Inc. |
| Steam App Id | 578080 |
5. Overwatch®
Overwatch®, A FUTURE WORTH FIGHTING FOR! Overwatch® is an always-on and ever-evolving free-to-play, team-based action game set in an optimistic future, where every match is the ultimate 5v5 or 6v6 battlefield brawl.
Overwatch® has achieved a Player Score of 27, placing it in the #5 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 370,443 reviews on Steam. This breaks down to a total of 98,652 positive reviews and 271,791 negative reviews — making it "Mostly Negative" on Steam.
It can be played and ran on Windows systems. At the moment, it is possible to play Overwatch® on the Steam Deck (though some functionality may be limited).
| Release Date | 8/10/2023 |
| Franchise | Blizzard |
| Developer | Blizzard Entertainment, Inc. |
| Publisher | Blizzard Entertainment, Inc. |
| Steam App Id | 2357570 |
6. Tom Clancy's Rainbow Six® Siege X
Rainbow Six Siege X is the reference in tactical team shooters, where elite strategy and execution triumph. Enjoy free access to Quick Match, Unranked and Dual Front game modes with a selection of operators.
Tom Clancy's Rainbow Six® Siege X has achieved a Player Score of 82, placing it in the #6 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 1,479,880 reviews on Steam. This breaks down to a total of 1,222,854 positive reviews and 257,026 negative reviews — making it "Very Positive" on Steam.
It can be played and ran on Windows systems. At the moment, it is not possible to play or run Tom Clancy's Rainbow Six® Siege X on the Steam Deck.
| Release Date | 12/1/2015 |
| Franchise | Tom Clancy Franchise |
| Developer | Ubisoft Montreal |
| Publisher | Ubisoft |
| Steam App Id | 359550 |
7. Warframe
Awaken as an unstoppable warrior and battle alongside your friends in this story-driven free-to-play online action game
Warframe has achieved a Player Score of 87, placing it in the #7 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 651,104 reviews on Steam. This breaks down to a total of 570,404 positive reviews and 80,700 negative reviews — making it "Very Positive" on Steam.
It can be played and ran on Windows systems. Valve has also verified it as playable on the Steam Deck and will run well.
| Release Date | 3/25/2013 |
| Developer | Digital Extremes |
| Publisher | Digital Extremes |
| Steam App Id | 230410 |
8. Delta Force
Delta Force, a free-to-play 1st-person tactical shooter, returns as the latest in the classic series. With 25 years defining the genre, Delta Force is back with an upgraded arsenal of weaponry, jaw-dropping environments, and a truly dynamic world.
Delta Force has achieved a Player Score of 58, placing it in the #8 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 171,973 reviews on Steam. This breaks down to a total of 100,616 positive reviews and 71,357 negative reviews — making it "Mixed" on Steam.
It can be played and ran on Windows systems. At the moment, it is not possible to play or run Delta Force on the Steam Deck.
| Release Date | 12/4/2024 |
| Developers | |
| Publisher | TiMi Studio Group |
| Steam App Id | 2507950 |
9. Team Fortress 2
Nine distinct classes provide a broad range of tactical abilities and personalities. Constantly updated with new game modes, maps, equipment and, most importantly, hats!
Team Fortress 2 has achieved a Player Score of 90, placing it in the #9 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 1,215,979 reviews on Steam. This breaks down to a total of 1,103,559 positive reviews and 112,420 negative reviews — making it "Very Positive" on Steam.
It can be played and ran on both Windows and Linux systems. At the moment, it is possible to play Team Fortress 2 on the Steam Deck (though some functionality may be limited).
10. tModLoader
Dig, Fight, and Build your way through the world of player-created mods on Terraria with tModLoader - this DLC makes modding Terraria a reality!
tModLoader has achieved a Player Score of 96, placing it in the #10 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 355,138 reviews on Steam. This breaks down to a total of 344,972 positive reviews and 10,166 negative reviews — making it "Overwhelmingly Positive" on Steam.
It can be played and ran on Windows, Mac, and Linux systems. At the moment, it is possible to play tModLoader on the Steam Deck (though some functionality may be limited).
More Free Online Co-Op Games
Explore even more rankings for the 100 best free Online Co-Op games available on Steam.
| Image | Name | Actions | ||||
|---|---|---|---|---|---|---|
| 759,684 | 8/21/2012 | 86 | Free | Steam Charts | |
| 475,065 | 7/9/2013 | 81 | Free | Steam Charts | |
| 129,645 | 12/6/2024 | 77 | Free | Steam Charts | |
| 127,371 | 12/21/2017 | 60 | Free | Steam Charts | |
| 101,397 | 8/10/2023 | 27 | Free | Steam Charts | |
| 58,823 | 12/1/2015 | 82 | Free | Steam Charts | |
| 58,748 | 3/25/2013 | 87 | Free | Steam Charts | |
| 56,032 | 12/4/2024 | 58 | Free | Steam Charts | |
| 53,536 | 10/10/2007 | 90 | Free | Steam Charts | |
| 45,237 | 5/16/2020 | 96 | Free | Steam Charts | |
 | 30,203 | 11/14/2025 | 86 | Free | Steam Charts | |
 | 12,682 | 7/9/2024 | 76 | Free | Steam Charts | |
 | 12,526 | 12/8/2023 | 78 | Free | Steam Charts | |
 | 11,421 | 9/30/2021 | 50 | Free | Steam Charts | |
 | 11,324 | 10/17/2017 | 80 | Free | Steam Charts | |
 | 7,258 | 8/27/2024 | 55 | Free | Steam Charts | |
 | 7,208 | 7/17/2025 | 54 | Free | Steam Charts | |
 | 7,057 | 6/7/2024 | 64 | Free | Steam Charts | |
 | 6,921 | 11/15/2017 | 76 | Free | Steam Charts | |
 | 6,920 | 10/23/2013 | 88 | Free | Steam Charts |
Soures & References
Steambase has best-in-class data powered directly by Steam, our data partners, and in-house experts. Player counts and rankings are enriched, analyzed, and updated in real-time to ensure we surface the most up-to-date insights. Learn more about the Steambase approach to data collection and our review methodology.
- Valve Corporation. (2026, February 13). Steam Store. Steam Store.
- Valve Corporation. (2026, February 13). Counter-Strike 2 on Steam. Steam Store.
- Valve Corporation. (2026, February 14). Dota 2 on Steam. Steam Store.
- Valve Corporation. (2026, February 15). Marvel Rivals on Steam. Steam Store.
- Valve Corporation. (2026, February 11). PUBG: BATTLEGROUNDS on Steam. Steam Store.
- Valve Corporation. (2026, February 13). Overwatch® on Steam. Steam Store.
- Valve Corporation. (2026, February 14). Tom Clancy's Rainbow Six® Siege X on Steam. Steam Store.
- Valve Corporation. (2026, February 14). Warframe on Steam. Steam Store.
- Valve Corporation. (2026, February 15). Delta Force on Steam. Steam Store.
- Valve Corporation. (2026, February 12). Team Fortress 2 on Steam. Steam Store.
- Valve Corporation. (2026, February 12). tModLoader on Steam. Steam Store.