Toby Fox has previously stated the game will have only one ending. However, on Deltarune's Steam page, the statement is worded somewhat mysteriously, and another route has been discovered in Chapter 2.

I will resolve this question to YES if the full version of the game (including all chapters) has just one ending. I will not count a few changed lines of dialogue as a different ending, it needs to be clearly distinct. Additionally, this question is only about the ending of the game, and not about any possible divergences before that point (e.g., if taking the Snowgrave route in Chapter 2 leads to the same end as taking any other route, this question will be resolved to YES).

If Deltarune is never fully released, this will be resolved to N/A.