No financial institution or legitimate company will contact you by phone or email to ask for your social security number, credit card number or other personal information.

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Typically they ask the recipient to supply confidential information, like a username, password, social security number, or credit card number.

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The dream is that, eventually, everything about you--name, address, Social Security number, credit card accounts, medical history and more--will be instantly recognized and ready for secure delivery to a vendor with whom you'd like to do business.

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Don't carry your Social Security card around and never give the number out to any business that asks for it.

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Mobile users can also be duped through so-called "smishing" -- a combination of the words SMS and phishing -- where a user receives a text message asking for personal information like a credit card number, e-mail address or social security number.

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If you have a Medicare card, make a photocopy without the last 4 digits of your Social Security number.

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BillMeLater, for example, doesn't require a credit card or debit card number, but it does ask for a customer's Social Security number and date of birth.

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But you might find it difficult to set up a new account until you have suitable personal identification in your new destination (such as a job or rental contract or social security number in the US), so make sure you have a decent credit card with zero foreign transaction fees to get you through the first few weeks.

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If you do not have a Social Security Number for your dependent, and your dependent qualifies for a Social Security Number, you need to file a form SS5, Application for a Social Security Card (downloads as a pdf), with the Social Security Administration (SSA).

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