A background report can be run without a Social Security Number if there is no one available. However, if an individual does have a Social Security number or an ITIN number, it is highly recommended that they use that when pulling their reports. That critical piece of information helps narrow down what records are related to you verse related to another person with a similar name or date of birth. In addition, having a Social Security number or ITIN, it can drastically reduce the errors and incorrect information you'll see on a background report.