Your U.S. social security benefits may not be taxable in the United States.
Residents of the following countries are exempt from US tax on their US social security benefits: Canada, Egypt, Germany, Ireland, Israel, Italy (you must also be a citizen of Italy for the exemption to apply), Romania or the United Kingdom.
Per the U.S. tax treaties with the above mentioned countries, US social security benefits are only taxable in the expat’s country of residence, not in the US. So this year when you receive your 1099SSA, make sure its first stop is the taxing authority of your new country of residence!