Yes, you can upgrade your Delta SkyMiles® Gold American Express Card to the Delta SkyMiles® Platinum American Express Card, but it is important to understand the process and the trade-offs. You can typically initiate an "upgrade" by calling American Express customer service or checking the "Amex Offers" section of your online account for a targeted upgrade promotion. In 2026, the Delta Platinum card has a significantly higher annual fee (currently $350) compared to the Gold card, but it offers enhanced benefits such as an annual Companion Certificate (for domestic main cabin round-trips), higher earn rates on Delta and hotel purchases, and a statement credit for Global Entry or TSA PreCheck. A major benefit of upgrading is the ability to earn MQDs (Medallion Qualification Dollars) toward Delta elite status, which the Gold card does not offer. However, be aware that "upgrading" an existing card usually does not grant you the same massive "Welcome Bonus" miles that you would receive by applying for the Platinum card as a brand-new account. Before switching, many experts recommend checking if you are eligible for an upgrade bonus that could offset the increased fee.