There are multiple categories with which the citizen candidate can apply for U.S. citizenship. And eligibility requirements for naturalization vary according to the category the candidate is under. To reach the categories and investigate their specific requirements, please see Citizenship and Naturalization
However, there are still common requirements that every candidate must meet to be eligible for naturalization:
Listed requirements with a star symbol (*) means that there are exceptions to them based on military service
- The citizen candidate must be a Green Cardholder,
- (The time you must spend as a permanent resident in the U.S. varies according to your category)
- The citizen candidate must complete his/her category’s wait time after the Green Card is issued*
- The citizen candidate must be at least 18 years of age
- The citizen candidate must not take trips six months or longer outside of the U.S. during his/her designated wait time before naturalization application
- The citizen candidate must have been residing in the state s/he applies for naturalization for at least 3 months
- The citizen candidate must have a good moral character. To better understand ‘what having a good moral character’ entails, please see this PDF file. (Starting with page 9)
- The citizen candidate must successfully complete the English language test and the civics test.*
- (To see the exceptions and accommodations granted for certain individuals on naturalization examinations, please see this link.)
- The citizen candidate must accept to serve in the U.S. when called upon for national duty.
- The citizen candidate must be willing to protect the Constitution of the U.S.