Agreement between the Government of the United States of America and the Government of Canada with respect to Social Security. A Canadian Social Insurance Number is not a valid TIN (Taxpayer Identification Number) for the purposes of the US tax reporting and withholding regimes.Introduction. This booklet explains how being outside the United States may affect your Social. Totalization agreements have three main purposes. This publication provides information on the income tax treaty between the United States and Canada. USAID is the United States' government agency that leads international development and humanitarian assistance efforts to partner countries. Travel insurance is not accepted. To complete ID checks, Customs and Immigration closes the gates 15 minutes before the scheduled departure; gates will not reopen once closed. USAID's investments help achieve sustainable development progress, advancing our collective security, health, and prosperity. Preamble. The States Parties to the present Covenant,.