Note: These SIN and BN validation tests will determine if the submitted number passes the check digit formula for a Canadian Social Insurance Number (SIN) or Business Number (BN). These tests will NOT ensure that the number is an actual valid SIN or BN issued to an individual or business. You may use these validation tests to determine if a submitted SIN or BN is in the correct format and to ensure that the numbers have not been accidentally changed (e.g. digit transposition or mis-read).