US Social Security taxes while working for Canadian employer but living in third country

Question

https://stackoverflow.blog/2021/02/19/podcast-314-how-do-digital-nomads-pay-their-taxes/ got me thinking, how would a United States citizen, living in Taiwan (which has no Social Security totalization agreement with the US) working for a Canadian company online, pay their Social Security contributions? To make things more complicated, the US and Canada have a Social Security totalization agreement.

Also let's say this person already has 5 years, 20 credits and needs five more years, 20 more credits, to reach the 40 credit threshold for receiving US Social Security benefits.

So might the Canadian company report the earnings to Canada, or perhaps the US citizen will be better off filing as self-employed and paying the Social Security taxes directly himself? Etc.

Or maybe he can't make contributions even if he wants to, because he is not working for US company, or present in the United states?

See also https://www.irs.gov/individuals/international-taxpayers/persons-employed-by-a-foreign-employer .

Answer 1

It appears that Canada is a red-herring in this question. Canada doesn't tax non-residents on earned income, and if your employer makes deductions you should claim refund (see here).

From the US tax perspective, if you're resident in a foreign country and are working for a foreign employer you do not pay your social security taxes, as described in the IRS link you've provided.

If you're self-employed, then you're paying the SE tax regardless of where you live.