Eligibility requirements for Naturalization Form N400

 Here's what you should know:

1. The applicant should have maintained continuous residence in the U.S. for at least five years before filing for N-400.

2.  Even if the applicant is not physically present in the U.S. for the number of years specified, he should maintain status as a legal permanent resident, maintaining a U.S. address and paying his or her State and Federal taxes as part of the eligibility requirement while applying for citizenship.

3. If the applicant wants to be abroad for several months, he may file form I-470 (Application to Preserve Residence for Naturalization Purposes, prior to leaving the U.S. so that they may be able to preserve their status.

4. After being married to a U.S. citizen, the applicants should have stayed continuously for three years before filing the N-400.
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