Undertale gains immense popularity, becoming a phenomenon within the gaming community. Fan art, fanfiction, and cosplay based on the game flood the internet.

Undertale receives numerous awards and nominations, including nominations for Game of the Year from various publications and winning awards for Best RPG.

Undertale's impact on game design and storytelling continues to be felt years after its release. It inspires other indie developers to experiment with unconventional narratives and gameplay mechanics.