Terraria is not free. It is a paid game that typically costs $9.99 USD on PC (via Steam), with similar or slightly varying prices on consoles (PlayStation, Xbox, Nintendo Switch) and mobile devices (iOS, Android). However, it is frequently discounted during seasonal sales, sometimes dropping to as low as $4.99 or less. While it is not free-to-play, the game offers exceptional value for its price, providing hundreds of hours of content, regular updates (including the final major update, "Journey's End"), and no microtransactions or paywalls. The only way to play Terraria at no cost would be through a friend’s shared library on Steam (if they enable family sharing), or by accessing it via certain subscription services like Xbox Game Pass, where it is included as part of the monthly fee. But in direct terms—no, you cannot legally download and play Terraria for free without a paid purchase or subscription.