American Express miles are earned by cardholders who make purchases with a Delta credit card issued by American Express. American Express also has credit cards that give rewards points, rather than miles, and those Amex points can be transferred to airline partners or redeemed for travel through Amex Membership Rewards.
American Express Miles for Delta Airlines
Each Delta SkyMiles American Express card gives miles at a different rate when cardholders make purchases. Higher tier cards like the Delta SkyMiles Platinum American Express Cardand the Delta SkyMiles Reserve American Express Card give more miles through better intro bonuses and ongoing bonus rewards rates, but also come with high annual fees.
Cardholders can redeem their SkyMiles for travel-related expenses through their Delta SkyMiles account. These Amex miles are worth over 1 cent per mile.
Using Amex Points for Airfare
Amex rewards points can be spent on travel-related purchases through the Membership Rewards portal or transferred to any of Amex's 17 partner airlines, including Emirates, Aer Lingus, and JetBlue. Once you've transferred your Amex points to an airline's miles, you'll usually be able to find them in your account with the partner airline within a few days.
Delta is one of Amex's partner airlines, by the way. With Delta, Membership Rewards points can be turned into SkyMiles at a 1:1 ratio. The miles will generally take less than 30 minutes to appear in your Delta account.