Blood Harmony is the debut extended play by American singer-songwriter Finneas. It was released by his record label OYOY, distributed by AWAL, on October 4, 2019. All of the material on the EP was produced and written by Finneas.

Blood Harmony was supported by the release of four singles, from 2018 to 2019. The lead single, "Let's Fall in Love for the Night" peaked at numbers 17 and 24 on the US Billboard Alternative Songs and Rock Airplay charts, respectively. Finneas toured the United States throughout October 2019 in support of the EP. A deluxe edition was released on August 7, 2020, featuring the 2018 single "Break My Heart Again" and a new version of "Let's Fall in Love for the Night" entitled "Let's Fall in Love for the Night (1964)". The EP peaked at number 14 on the US Heatseekers Albums chart and number 47 on the Lithuanian Albums chart.