Free alternatives
Free Alternatives to Cities: Skylines & Transport Tycoon
Short answer
OpenTTD is the best free alternative to Cities: Skylines and Transport Tycoon: a free, open-source transport network simulation in continuous development since 2004, with multiplayer and a vast official add-on library.
Network-building simulation — routes, logistics, watching a system you designed slowly come to life — has one outstanding free option, and it has been refined continuously for over two decades.
Our pick: OpenTTD
SimulationStrategy200 MBOpen Source (GPL-2.0)
OpenTTD is an open-source rebuild of Transport Tycoon Deluxe with 25 years of improvements: enormous maps, multiplayer, and a colossal library of add-on content through its in-game download service.
How it differs from Cities: Skylines: Transport networks rather than city zoning. You do not paint residential districts; you connect the towns that already exist and grow them through service.
All free Cities: Skylines alternatives compared
OpenTTD
OpenTTD is an open-source rebuild of Transport Tycoon Deluxe with 25 years of improvements: enormous maps, multiplayer, and a colossal library of add-on content through its in-game download service.
The difference: Transport networks rather than city zoning. You do not paint residential districts; you connect the towns that already exist and grow them through service.
OpenTTD is dangerously easy to underestimate. It looks like an old transport game, and then you realize you've spent two hours redesigning a rail network because one coal mine is producing more cargo than your entire system can handle. We picked it because its simple premise hides an absurdly satisfying optimization game.
Luanti
If the appeal is building a settlement from nothing, Luanti's voxel sandbox gives you unlimited terrain and hundreds of building-focused game modes.
The difference: First-person voxel construction, not top-down management. No simulation of citizens or economy.
Luanti stopped being a Minecraft alternative a long time ago—and that's exactly why we picked it. What began as a simple voxel experiment has evolved into an open platform where completely different games can live inside the same engine. The sheer amount of player-made content makes it feel less like one game and more like a tiny open-source game ecosystem.
Mindustry
Mindustry is the logistics half of the appeal distilled: conveyor networks, resource chains and throughput optimisation, with combat pressure on top.
The difference: Factory logistics rather than civic simulation, and it is an actively hostile environment — things attack your network.
Mindustry is what happens when a tower defense game decides it wants to be a factory simulator and then accidentally becomes an RTS. We picked it because it keeps adding another layer—mining, logistics, production, power, defenses, research—until you're no longer defending a base so much as operating an increasingly ridiculous industrial machine.
Questions
What is the best free alternative to Cities: Skylines?
OpenTTD is the best free alternative to Cities: Skylines and Transport Tycoon: a free, open-source transport network simulation in continuous development since 2004, with multiplayer and a vast official add-on library.
Are these Cities: Skylines alternatives really free?
Yes. Every game listed here is free to start, with no trial masquerading as a full game and no paid competitive advantage. Optional cosmetics and premium extras are allowed. Each game has been tested and played, then assessed against PlayBound's four published criteria — including whether it has That One Thing worth telling a friend about.
Do I need to pay for multiplayer in these Cities: Skylines alternatives?
No. None of these games charge for multiplayer. Public servers are community-run and free to join, and there is no subscription of any kind.
How is OpenTTD different from Cities: Skylines?
Transport networks rather than city zoning. You do not paint residential districts; you connect the towns that already exist and grow them through service.
How is Luanti different from Cities: Skylines?
First-person voxel construction, not top-down management. No simulation of citizens or economy.
How is Mindustry different from Cities: Skylines?
Factory logistics rather than civic simulation, and it is an actively hostile environment — things attack your network.
Every game here has been assessed against the PlayBound Bar — four published criteria for whether a free game is actually worth your time. Every title is tested and played before it is added.