How to Find the Security Number of a Credit Card
- 1). Look on the back. For Visa, MasterCard and Discover Card holders, this will be a three-digit number on the right side of the signature strip.
- 2). Look on the front. For American Express holders, this will be a four-digit number on either the left or right side of the card.
- 3). Contact your credit card company or bank if the number has worn off. They will issue you a new card.
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