Social security card
If you haven't yet, memorize those all-important nine digits, as this card is the number one worst item to tote around. It gives a thief the information he needs to do everything from buying a car to opening a new credit card account to taking out a loan in your name. Remember, your social security number is unique to you and can't be easily canceled like a credit card — which gives you little recourse should it fall into the wrong hands. Be mindful, too, of carrying anything else that may have your social security number on it. That includes Medicare cards that were issued before April 2015; a good work-around is to carry a photocopy instead, and black out the sensitive info.
Password cheat sheet
We all have more logins and passwords than we can possibly remember, but keeping a cheat sheet in your wallet is not the answer. Especially if some of those passwords are tied to bank or retail accounts where your credit card information is saved. If you must write down your passwords, leave the information in a secure place at home, or consider an encrypted mobile app to help you manage them.
It may not be your go-to payment method, but even keeping a check in your wallet "just in case" isn't a good idea. For starters, it gives thieves a direct line to your checking account; they just have to fill it out and then cash in. Checks also have your routing and account numbers printed on them — information that could be used to electronically transfer funds out of your account. The solution: Carry checks only when needed, and no more than the amount that you need.
Extra credit and debit cards
You only need two. At most. Carry whichever ones you use most frequently and leave the rest at home. This not only limits the cards that a thief has at his disposal, but also makes it easier for you when you're trying to cancel cards or follow up on fraudulent charges.
This one is not only about lightening your wallet load. While businesses aren't allowed to include complete credit card numbers on receipts, they can print the last five digits — which, along with the merchant information, is enough for a sophisticated thief to do some damage. Receipts also may have your signature on them. Get in the habit of clearing yours out every week. Either reconcile them at that time against your bank account or credit card statement, or save them somewhere until the end of the month and do it then. You could also go digital with a receipt tracking app.
Passport and birth certificate
At it stands, these might not seem like everyday wallet items. But really, neither should ever be kept in your wallet — even on days when you need to use them. Both open the door onto a world of possibilities for thieves; they can even be used to get a new copy of your social security card (see above for where that can lead). If you need to present your birth certificate, carry it somewhere safe and separate. As for your passport, when you're in the U.S., a driver's license or other personal ID should suffice for everyday identification. When you're out of the country, put your passport in the hotel safe and walk around with only a photocopy.
Keep them at home until the day you know you're going to use them. Otherwise, you're handing thieves free money.
Some people tuck a spare into their billfold or a zippered wallet pocket, but that's giving thieves the keys to the kingdom — literally.