Free Online Co-Op Games on Steam
Steam currently has 9,245 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 5/8/2026.
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 9,580,545 reviews on Steam. This breaks down to a total of 8,254,690 positive reviews and 1,325,855 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 2,706,371 reviews on Steam. This breaks down to a total of 2,188,322 positive reviews and 518,049 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. 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 #3 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 2,708,153 reviews on Steam. This breaks down to a total of 1,632,953 positive reviews and 1,075,200 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 |
4. 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 #4 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 181,087 reviews on Steam. This breaks down to a total of 105,540 positive reviews and 75,547 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 |
5. World of Warships
Immerse yourself in thrilling naval battles and assemble an armada of over 800 ships from the first half of the 20th century — from stealthy destroyers to gigantic battleships. Change the look of your ship, choose upgrades to suit your play style, and go into battle with other players!
World of Warships has achieved a Player Score of 76, placing it in the #5 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 154,341 reviews on Steam. This breaks down to a total of 118,229 positive reviews and 36,112 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 World of Warships on the Steam Deck (though some functionality may be limited).
| Release Date | 11/15/2017 |
| Franchise | World of Warships Franchise |
| Developer | Wargaming Group Limited |
| Publisher | Wargaming Group Limited |
| Steam App Id | 552990 |
6. 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 #6 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 661,351 reviews on Steam. This breaks down to a total of 580,005 positive reviews and 81,346 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 |
| Franchise | Digital Extremes Ltd. |
| Developer | Digital Extremes |
| Publisher | Digital Extremes |
| Steam App Id | 230410 |
7. 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 #7 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 1,229,571 reviews on Steam. This breaks down to a total of 1,117,692 positive reviews and 111,879 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).
8. 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 76, placing it in the #8 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 385,480 reviews on Steam. This breaks down to a total of 295,497 positive reviews and 89,983 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 |
9. Tom Clancy's Rainbow Six Siege
Rainbow Six® Siege 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 has achieved a Player Score of 82, placing it in the #9 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 1,509,292 reviews on Steam. This breaks down to a total of 1,244,638 positive reviews and 264,654 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 on the Steam Deck.
| Release Date | 12/1/2015 |
| Franchise | Tom Clancy Franchise |
| Developer | Ubisoft Montreal |
| Publisher | Ubisoft |
| Steam App Id | 359550 |
10. 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 30, placing it in the #10 spot for the best free Online Co-Op games. Its score was calculated by analyzing a total of 398,226 reviews on Steam. This breaks down to a total of 118,909 positive reviews and 279,317 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 |
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 | ||||
|---|---|---|---|---|---|---|
| 690,032 | 8/21/2012 | 86 | Free | Steam Charts | |
| 324,774 | 7/9/2013 | 81 | Free | Steam Charts | |
| 312,595 | 12/21/2017 | 60 | Free | Steam Charts | |
| 92,227 | 12/4/2024 | 58 | Free | Steam Charts | |
| 47,899 | 11/15/2017 | 76 | Free | Steam Charts | |
| 43,788 | 3/25/2013 | 87 | Free | Steam Charts | |
| 43,699 | 10/10/2007 | 90 | Free | Steam Charts | |
| 37,170 | 12/6/2024 | 76 | Free | Steam Charts | |
| 33,890 | 12/1/2015 | 82 | Free | Steam Charts | |
| 30,280 | 8/10/2023 | 30 | Free | Steam Charts | |
 | 16,468 | 5/16/2020 | 96 | Free | Steam Charts | |
 | 12,531 | 11/14/2025 | 86 | Free | Steam Charts | |
 | 8,648 | 9/30/2021 | 50 | Free | Steam Charts | |
 | 8,445 | 7/9/2024 | 77 | Free | Steam Charts | |
 | 6,807 | 12/7/2023 | 78 | Free | Steam Charts | |
 | 6,456 | 10/23/2013 | 88 | Free | Steam Charts | |
 | 5,441 | 3/16/2026 | 59 | Free | Steam Charts | |
 | 5,398 | 7/17/2025 | 55 | Free | Steam Charts | |
 | 5,211 | 10/17/2017 | 80 | Free | Steam Charts | |
 | 3,809 | 3/25/2024 | 85 | 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, May 8). Steam Store. Steam Store.
- Valve Corporation. (2026, May 8). Counter-Strike 2 on Steam. Steam Store.
- Valve Corporation. (2026, May 8). Dota 2 on Steam. Steam Store.
- Valve Corporation. (2026, April 29). PUBG: BATTLEGROUNDS on Steam. Steam Store.
- Valve Corporation. (2026, May 8). Delta Force on Steam. Steam Store.
- Valve Corporation. (2026, May 6). World of Warships on Steam. Steam Store.
- Valve Corporation. (2026, May 5). Warframe on Steam. Steam Store.
- Valve Corporation. (2026, April 17). Team Fortress 2 on Steam. Steam Store.
- Valve Corporation. (2026, May 7). Marvel Rivals on Steam. Steam Store.
- Valve Corporation. (2026, May 8). Tom Clancy's Rainbow Six Siege on Steam. Steam Store.
- Valve Corporation. (2026, May 6). Overwatch® on Steam. Steam Store.