: Your full 16-digit card number is located on the front of your physical card. If you don't have the card yet, you can sometimes find the number (often masked) on your monthly billing statements or within your Citibank Account Online portal.
If you recently applied and are waiting for a decision, you can check your status: best buy credit card lookup
If you need to find a past purchase receipt using your credit card: : Your full 16-digit card number is located