CNET: Is it Safe to Share Your Social Security Number? Experts Explain the Risks

Your Social Security number is also going to be mandatory for anything that triggers tax reporting, including your employer reporting your wages to the IRS, said Alan Butler, executive director of the Electronic Privacy Information Center, a nonprofit focused on defending privacy and identity rights. 

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If they won’t budge and you’re not comfortable giving them your personal information, then don’t. “Every time another entity stores your Social, it’s one more chance for identity theft,” said Butler. 

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