According to The Guide to Naturalization by USCIS , the 5-year continuous residence is defined as : "5 years as a Permanent Resident without leaving the US for trips of 6 months or longer" the guide also states that : "Continuous Residence may be broken if you take a single trip out of the country that lasts 6 months or more" My question is : Is it the combined time outside of the country can't be more than 6 months within a year? If so, does it count from Jan 1st of every year? I've stayed outside of US from 1/15/2010 to 5/3/2010 (108 days), does that mean i have 72 days left for 2010 if I wish to travel outside of the US again this year? i was reminded at the port of entry that if i stay more than 6 months i could lose my GC. please post your source if you know the answers, thanks for reading.