The season finale (episode 21, titled 'Thank You') of the fourteenth season of the American procedural drama television series Chicago Fire, which originally premiered on NBC on October 1, 2025, and concluded on May 13, 2026. The episode features high-stakes drama at Firehouse 51, including a major disaster call with a roof collapse, Severide's career crossroads, surprise visitors for key characters, and emotional farewells.

A pivotal episode marking significant changes for the long-running series, often discussed by fans for its twists, character developments, and cliffhanger potential leading into future seasons.