I became Canadian citizen in 2005. I am working in the USA since 2006 on TN Visa and will retire after 5 years. I am paying both Canadian and US taxes. After retirement, I am planning to settle in Canada. Will I be eligible to get OAS and GIS (keeping view of requirement of minimum 10 year residency in Canada)? In other words, working in the USA on TN visa and paying Canadian taxes will be considered as ‘resedency’?

Tax residency, physical residency and immigration residency are all indpendently different topics. OAS might be subject to physical residency; tax residency may not be sufficient. Patrickm might be able to shed more light on this.

However, if you work 10 years worth (40 quarters, consecutive not required) in the US, you will be eligible for Social Security benefits per tax treaty, assuming social security does not go bankrupt by then.

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Dimple2001

Right, all three are very different concepts govered by different agencies.
Tax residency is perhaps the most complicated and the area with most "grey".

You haven't given much information about the location of your financial assets, etc. but if you have a home, driver's license, utilities, bank accounts, brokerage accounts, etc. in Canada you are most certainly a "deemed resident" for tax purposes.

To fully ascertain your status from tax purposes, please review:
http://www.cra-arc.gc.ca/E/pub/tp/it221r3-consolid/README.html

However, OAS eligibility requires physical residency.
For requirements, refer:
http://www.servicecanada.gc.ca/eng/isp/pub/oas/oas.shtml

There is another complication : for a particular year to be counted towards OAS eligibility, you need to physically reside in Canada for more than 182 days of that year.
Therefore, if you have been traveling back and forth a lot, you may miss out several years towards your OAS eligibility criteria.

How long is your total residency in Canada?
Did you apply for Canadian citizenship soon after completing the required 3 years?

If you are only a couple of years short, you can of course wait to apply for OAS.
However, there are several other age benefits/credits that will get impacted that are dependent upon having applied for OAS

I think it is best to call Service Canada to discuss your specific situation and the impact of your US social security contributions (contact information in the link above).

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