“合众为一”（拉丁语：E pluribus unum，英语：Out of Many, One）是美国国徽上的格言之一，出现在国徽的正面。该格言由皮埃尔-尤金·迪西默蒂埃（Pierre Eugene du Simitiere）提议，于1776年被加入美国国徽，并于1782年经国会法案决议采用。“合众为一”最先出现在一首名为《Moretum》的诗歌当中，相传该诗为维吉尔（Publius Vergilius Maro）所作，但他可能并非真正的作者。在诗歌中，“color est e pluribus unus”描述了将各种颜色混为一色。

E pluribus unum (/ˈiː ˈplʊərᵻbəs ˈuːnəm/; Latin: [ˈeː ˈpluːrɪbʊs ˈuːnʊ̃])—Latin for "Out of many, one" (alternatively translated as "One out of many" or "One from many")—is a phrase on the Seal of the United States, along with Annuit cœptis (Latin for "He approves (has approved) of the undertakings") and Novus ordo seclorum (Latin for "New Order of the Ages"), and adopted by an Act of Congress in 1782. Never codified by law, E Pluribus Unum was considered a de facto motto of the United States until 1956 when the United States Congress passed an act (H. J. Resolution 396), adopting "In God we trust" as the official motto.