The American Express Platinum card has no pre-set credit limit. That does not give cardholders unlimited purchasing power. It means American Express won’t give you a specific credit limit once you’re approved for the card. Rather, they calculate your purchasing power based on how much you spend on the card as well as your income, any debt you carry, and your overall creditworthiness. Most Amex Platinum cardholders report a credit limit of $2,500 or so for the first several months, from what they can tell.
While “no pre-set limit” can sound enticing, it can actually be quite dangerous. Credit utilization is a major factor in how your credit score is calculated. Essentially, “credit utilization” refers to how much of your credit limit you’re using each month. The less you use up, the better it is for your credit score. However, cards that have no pre-set limit make it extremely difficult to determine your credit utilization. They have the potential to hurt your credit score as a result.
You also have to consider things in even more practical terms. If you don’t know what your credit limit is, you won’t know when you’re approaching it. That could leave you in a tough spot in an emergency situation and make it difficult to buy high priced items with confidence. Thankfully, many cardholders have reported getting emails or calls from Amex early on, saying they were approaching their spending threshold and would need to make a payment before being allowed to make any more purchases.
The best thing to do when trying to figure out how much you can spend on your Amex Platinum card is to start small and gradually increase your spending over time. You will have to pay your balance in full every month, anyway, since Amex Platinum is a charge card. Many cards offering “no pre-set limit” are charge cards.