The gas station charged you $100 on your credit card likely because you paid for the gas at the pump. When doing so, gas stations place a temporary hold on your card, to ensure that you have enough funds to cover the purchase.
The good news is that you will only be billed for the amount of gas that you pumped, and the hold will be released, usually within a few days. If you notice the $100 charge remaining for more than a few days, you should contact your credit card issuer for assistance.
To avoid a credit card hold when fueling up, go inside the store and pay upfront, instead. You can determine your payment amount ahead of time and pay for the purchase using your credit card.
This answer was first published on 07/02/24. For the most current information about a financial product, you should always check and confirm accuracy with the offering financial institution. Editorial and user-generated content is not provided, reviewed or endorsed by any company.