Elderberry, the fruit of Sambucus nigra, has become a popular inclusion in foods, beverages, supplements, and more in recent years. Although the European subspecies, S. nigra ssp. nigra, has been widely studied for its composition, particularly for phenolic and volatile profiles, other subspecies, such as the American elderberry S. nigra ssp. canadensis and the blue elderberry S. nigra ssp. cerulea, have also become contenders in the elderberry supply chain. For the first time, the composition (including micronutrients, macronutrients, organic acids, titratable acid, soluble solids, phenolic compounds, and cyanogenic glycosides) of these three subspecies of elderberry is compared, highlighting the unique qualities of each subspecies and identifying gaps in the available data on the three subspecies. Expected final online publication date for the Annual Review of Food Science and Technology, Volume 15 is April 2024. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.