If a Canadian citizen decides to spend retirement years outside Canada, do they still get the full amount for CPP/OAS? or do they need to have residence in Canada?
I believe the answer depends on how long you have worked in Canada, the country in which you are currently residing and the social security agreement between the two.
For OAS I think, as long as you've worked at least 20 years in Canada (after the age of 18) you are entitled to the full amount.
For CPP It will depend on how many years you've contributed. You have to contribute to the CPP for at least one-third of all the years of your “contributory period”.
It could be more complex depending on your particular circumstances. For more information: http://www.servicecanada.gc.ca/eng/services/pensions/international/index.shtml