The Consumer Financial Protection Bureau has proposed new rules that would lower overdraft fees, with President Joe Biden calling the charges “exploitative.” Currently, the fee for overdrawing a bank account averages more than $26.

If a bank temporarily lends a consumer money when their account has reached a zero balance, the consumer is typically responsible for paying back both the overdrawn amount and an additional fee, which can be more than the original amount charged. In one example often cited by opponents of the fees, a $3 cup of coffee can end up costing someone $30.

Here’s what to know.