As noted in GN 01715.020, a person must have credit for at least 10 years of residence in Canada to receive
                  an OAS benefit while in Canada and credit for at least 20 years of residence in Canada
                  to receive an OAS benefit while outside Canada. Under the agreement, if a person resided
                  in Canada for at least 1 year, but not long enough to meet the 10-year or 20-year
                  requirements, the person’s years of coverage under the U.S. Social Security system
                  can be added to his or her years of residence in Canada to meet the applicable requirement.
                  Thus, the agreement permits someone who meets the:
               
               
                  - 
                     
                        • 
                           10-year requirement based on combined coverage to receive an OAS benefit while in
                              Canada (and for up to 6 additional months after leaving Canada)
                            
 
 
- 
                     
                        • 
                           20-year requirement based on combined coverage to receive an OAS benefit without interruption
                              while living in the United States; i.e., the benefit will not be suspended if the
                              person is in the United States for longer than 6 months.
                            
 
 
When determining eligibility for an OAS benefit under the agreement, Canada will only
                  count a person’s U.S. quarters of coverage (QC’s) and periods of residence in Canada
                  credited after age 18 and after 1951 (the present OAS program began January 1, 1952).
                  This requirement applies even though Canada normally counts periods of Canadian residence
                  before 1952 when determining eligibility for regular OAS benefits under its domestic
                  law.