Cardholders between their 20s and 40s make up 75% of Amex's new accounts acquired on its two premium cards, Platinum and Gold.

American Express on Monday announced "major updates" are coming "later this year" to the U.S. Consumer and Business versions of its popular Platinum cards, which have annual fees of $695.

The issuer said that The Platinum Card® from American Express and The Business Platinum Card® from American Express will be receiving a full revamp later this year. Chase and Capital One are also updating their premium cards, so the competitive landscape may shift quickly.