At its core, Finch's Letters To You is a song about missing someone. The speaker is alone and empty, longing for someone to be with them, but they cannot be together because they are far away. The song takes the form of a letter, a written message to the absent person, in which the speaker expresses their deep longing and emotional pain.

Throughout the song, the speaker repeatedly asks the question, "Do you notice I'm gone?" This question is at the heart of their emotional turmoil - they wonder if the person they miss even realizes that they are gone. The line "Where do you run to so far away?" is also repeated, underscoring the distance that separates the two lovers.

The final verse of the song is particularly poignant. The speaker declares that they have found someone new and that they no longer need the person they were writing to. However, the repetition of "I want you to know that I miss you I miss you so" at the end of the chorus suggests that even though the speaker has moved on, they still feel a strong sense of loss and longing. Ultimately, the song is an ode to the difficulty of letting go of someone you once loved.