My father lives in a country that doesn't have a tax treaty (or whatever) with Canada and his government CPP cheques have an automatic 25% tax deduction. That said, there may be some recovery from annual filing. Sorry for not having more clear info in this regard. We are still in the process of trying to clean up this matter because a number of years ago, he was advised that as a non-resident, it was not required that he file Cdn taxes. So he didn't which resulted in an OAS clawback and no further OAS payments. Now, in order to get the OAS payments reinstated, we are filing all his back tax returns and have yet to find what the ultimate result will be. We've also been advised by employees of Rev Canada (once) that he will recover all of the past payments, and then another advice that he will only recover the 11 months previous to final RevCan acceptance of up to date filings. The only reason I'm telling this somewhat personal info is to mark my agreement that you really need to get correct tax advice . . . which may not come from RevCan. Can't stress strongly enough, that you should seek expert advice from a tax specialist CA.
A fish and a bird can fall in love, but where will they build their nest?