加入美国籍的誓言是最长、最为具体和最具限定性。从内容前，反映出美国移民国家的特性。而且必须要大声朗读，否则不批准。英文原文如下：

I hereby declare, on oath, that I absolutely and entirely renounce and abjure all allegiance and fidelity to any foreign prince, potentate, state, or sovereignty of whom or which I have heretofore been a subject or citizen; that I will support and defend the Constitution and laws of the United States of America against all enemies, foreign and domestic; that I will bear true faith and allegiance to the same; that I will bear arms on behalf of the United States when required by the law; that I will perform noncombatant service in the Armed Forces of the United States when required by the law; that I will perform work of national importance under civilian direction when required by the law; and that I take this obligation freely without any mental reservation or purpose of evasion; so help me God。

译文：

我宣誓：我完全彻底断绝并彻底放弃对我迄今为止所隶属或作为其公民的任何外国王子、当权者、国家或君主的效忠和忠诚；我将支持和捍卫美利坚合众国宪法和法律，反对国内外一切敌人；我将信念坚定，忠诚不渝；我将根据法律要求为美国拿起武器；我将根据法律要求在美国武装部队中执行非作战服务；我将根据法律要求，在文职政丨府领导下从事对国家具有重要性的工作。我自愿承担这一义务，毫无保留，决不逃避。帮助我吧，上帝！