Social Security number (SSN)

The employee’s Social Security number or EIN employer identification number.

• When you try to change an employee's SSN to an SSN that already exists in the database, Evolution asks if you want to save the data for the current employee to the existing employee.

• EE Entry tab of the Employee - Employee window

• W2 tab of the Employee - Employee window

• http://www.ssa.gov/ and  http://www.ssa.gov/pubs/10002.html.