American Express Company on April 21 will raise minimum late payment fees to $39 from $29 on certain U.S. Commercial Card accounts

, excluding Corporate Purchasing Cards and Corporate Platinum Cards. "A fee of $39 will be assessed at approximately 45 days past due, and each additional late fee assessed--at approximately 60, 90 or 120 days, etc.--will be the greater of $39 or 2.99 percent of the amount that remains unpaid," according to a spokeswoman. "As before, late fees will only be assessed when the amount of past due charges is greater than $35."