Making many small purchases on your credit card may lead lenders to lower your credit limit, said Papadimitriou.
Banks see this as risky behavior, because it might give the impression you have no other way of paying for a cup of coffee than to charge it.
On the other hand, a bank may boost your credit limit if it sees that you're spending thousands of dollars on luxury items every month.
"While this isn't the deciding factor, it's just one more thing they look at -- especially when determining whether to give customers a credit line decrease or increase," said Papadimitriou.
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