During the 2017 Equifax data breach, approximately how many social security numbers were exposed?

• A. 50 million
• B. 120 million
• C. 150 million
• D. 300 million

Answer: (C)

The scale of a data breach matters, especially when it comes to Social Security numbers, which are a primary, hard-to-change identifier used across financial, tax, and government systems. In the 2017 Equifax breach, the number of exposed SSNs was reported to be about 145 to 147 million people. When you round to a broad approximation, that figure sits closest to 150 million, which is why this option is the best match. This magnitude matters because once an SSN is leaked, it can fuel identity theft for years, since replacing a Social Security number isn’t an option.