How long i can stay outside the US and still apply for a Naturalization?

First of all let me thank everybody in finance for the attempt you will make to answer this question.
I am an italian citizen who got married to an American Woman (Us Citizen) 6 years ago. After 2 years of paperwork i finally received a 10 years green card that`s why i am a Permanent Resident Card holder. I work and live in the US for 7 years straight with coming back to my country (Italy) for time off not more then 30 days a year. This past October 2008 i had to come subsidise to Italy for various reasons and i am still here after five months, April 2009 will be my sixth month. I really don't want to stay away from the US for too long because i do not want to jeopardize my immigration status and i also want to apply for a naturalization when i come back to the US. So after a brief explanation here is my interview.
How long can i stay away from the US without a re-entry permit and also to be able to still apply for a Naturalization?
I want to precise that i own been already on www.uscis.gov but some info are very confusing who says 6 months and afterwards i have to get back into the states or smaller amount then a year to still be able to apply for naturalization. Anyway i hope you can help me out otherwise in the past the 6 months are up i must return to the US and at this moment i can't.

Thank you all!
Answers:   
This is from the www.uscis.gov site.

General Naturalization Requirements

Residence and Physical Presence

An applicant is eligible to file if, immediately preceding the file of the application, he or she:

has been lawfully admit for permanent residence (see preceding section);
has resided continuously as a lawful eternal resident in the U.S. for at least 5 years prior to filing next to no single absence from the United States of more than one year;
has been physically present contained by the United States for at least 30 months out of the previous five years (absences of more than six months but less than one year shall disrupt the applicant's continuity of residence unless the applicant can establish that he or she did not abandon his or her residence during such period)
have resided within a state or district for at least three months

So, stays outside the US of more than 6 months can be problematic, and you'd have to establish that it be never your intent to abandon your residency. If you continued to file and pay your US taxes, that's recurrently sufficient evidence in and of itself. Part of the confusion is that while stays of more than 6 months can disrupt your residency requirement, they don't always. in the cease, it's a judgement call on the part of USCIS and that can be difficult to predict. but you are allowed to provide additional evidence to support your application, if required.
1) you do not inevitability a re-entry permit if you plan to return to the Sates within one year since the time of your departure. I know you said you're working on 6 months in April.

2) You must be physically present within the States when you APPLY for a work permit, but not necessarily wait for its approval, unless the country you are going to / will return from is on the list of countries that require an applicant to travel through the bio-metrics prior to departure.

This is where you need to go to necessarily hear it from the horse's mouth :
1) www.uscis.gov
2) Forms
3) Application for a travel document - Form I-131

The information that I provided above is from this form, so avail yourself to it.

Also, you may call the US Citizenship and Immigration Services
They have an international toll free number which is 1-8OO-767-1833.
Talk with an officer and explain your situation. They're friendly and informative.


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