If you are a lawful permanent resident and if you always wanted to remain in the country on a permanent basis, you may choose the naturalization process that will allow you to become a US citizen. But you need to file Form N-400, for naturalization only if you believe that you meet all the requirements for US Citizenship through naturalization.
After you become a permanent resident of the United States, if you wish to become a US citizen, you must be careful while traveling abroad. If you travel outside the country for more than 6 months, that will break your continuous residency, you may not qualify for naturalization. However, a short trip may not affect your application for US citizenship.
There are few requirements that must be satisfied if you look forward to become a US citizen and one of the most important requirements, is the requirement related to continuous residency. To qualify for US citizenship through naturalization, you must prove that you have been living in the United States as a Green Card holder for the past five years. You must not have resided outside the country for a long period, during that five year period. And if you had traveled outside the United States for a prolonged period of time, you may not become eligible to apply for naturalization.
If you were granted lawful status in the country as a result of your marriage to a US citizen, you must prove that you had been a permanent resident of the country for a three year period and all the other categories of permanent residents must establish that they had resided in the country as Green Card holders for the past five years.
Moreover, you need to prove that you were present in the country for at least 30 months, out of the five year period. If you are the spouse of a US citizen, you need to prove that you were present in the country at least 18 months out of the three year period. You must still be married to the same US citizen and reside with the same US citizen spouse to qualify for naturalization.
You will have to mention the number of trips and the duration of each trip in your application for naturalization. Similarly, you will have to provide details about your trip such as the purpose of your trip. If you had traveled for more than a year, then you may not become eligible to file an application for naturalization. But you still have an option to file an application to preserve your residency for naturalization. You will have to submit evidence and prove that you had not traveled abroad with an intention of abandoning your lawful status in the country.
You may file an application for naturalization only if you meet the continuous residence and the physical presence requirements. While filing Form N-400 for US citizenship through naturalization, you will have to demonstrate that you meet both the requirements. Hence it is mandatory to remember that you may not become eligible for naturalization if you do not meet the continuous residence requirement.