It s 6 months, and that only applies to your being eligible for the New York City resident tuition rates.NYC Residency Requirements page1. New York City Residence RequirementFor purposes of determining resident tuition fee eligibility, students must have lived in New York State for the past year and must have had their principal place of residence in the City of New York for a period of six consecutive months immediately preceding the first day of classes for the semester with respect to which residency determination is made. They must also state their intention to maintain their principal place of residence in New York City permanently.2. Citizen Permanent Residents who meet the above requirements are eligible for the New York City resident tuition rates. These students must show their U.S passport, or birth certificate and Permanent Resident Cards (green cards).3. Certificate of Residence Requirement for Out-of-City New York State ResidentsAll residents of New York State are eligible for the New York City resident rate. Students must, however, obtain a Certificate of Residence from their County Treasurer��s Office. A Certificate of Residence is valid for one academic year from the date of issue.