If you only play Sea of Thieves and no other Game Pass titles, buying a permanent key code is cheaper after just 2–3 months. However, if you play many games on Game Pass, the subscription offers better value.
Each key code is tied to a specific activation platform—such as Steam, the Microsoft Store (Xbox/Windows), or the official Sea of Thieves website—and may also be restricted by region, so paying close attention to the fine print is essential.