It's pretty normal to memorize your 9 digit social security number, in the same way you know your phone number. Because the SSN card is a fundamental piece of

It's pretty normal to memorize your 9 digit social security number, in the same way you know your phone number. Because the SSN card is a fundamental piece of identity theft, it's common practice to NOT carry the number in your wallet. You never know when you'll need the number, and very rarely need the actual card. I don't think I've ever used my physical SSN card in the last 5 years, but I need to provide the number itself quite often, especially on financial, employment, and government documents. We still use paper checks, too. Good times.