The following items I carry in my wallet. I recently purchased an RFID blocking wallet due to privacy concerns over identity theft and surreptitious location tracking via the RFID chip built into many new credit and debit cards.
Prepaid Calling Card
When cell phones don’t work, a prepaid phone card is a cheap and convenient way to make a phone call from a pay phone. It also avoids running up the long distance bill of the helpful stranger who graciously let you use their home phone to make a call.
Also, note my recommendations elsewhere on this site about having an out of state contact (extended family member or friend) that your immediate family can check in with if you are separated during the disaster. A phone card is helpful to make those calls.
Phone Number List
Keep a sheet of paper with important phone numbers on it. Friends, family, insurance agents, and emergency services numbers are all helpful. While you may have the majority of those numbers stored in your cell phone, it may be dead, lost, or destroyed.
I carry a spare car key in my wallet. I can’t count the number of times it has saved me when I inadvertently locked the keys in the car. Something that can be a huge ordeal an expense (calling a locksmith and then waiting for two hours) simply becomes a non-issue if you have a spare key on you.
Magnetic Key Box
An alternative to carrying a spare car key in your wallet is to hide the key in a magnetic key box somewhere outside your car (such as behind the bumper). This strategy might work better for women who tend to lock their purse in the car which contains their keys and their wallet.
I use to carry a spare house key in my wallet as well, but noticed that I normally don’t have my wallet when I lock myself out of the house (for example, I go out the back door to take out the trash and the door blows shut). So, I have since placed a well hidden house key outside my residence instead of carrying one on my wallet.
Although most of our financial transactions are now electronic (credit and debit cards), cash is king in emergencies. Merchants need power and telecommunication connectivity to accept credit cards. Both are typically down in disasters.
It is best to have small bill denominations on hand. Carry at least one hundred dollars split between, $20s, $10s, $5s, and $1s (or whatever is appropriate in your local currency). Avoid large bills, like $50s and $100s, as it is hard to buy a $2 item with a $100 bill. Most people don’t have $98 of change on them! (You however, will now be an exception to that, right?)
Fold this stash up and hide it in a corner of your wallet so you won’t be tempted to use it for non emergency purposes.