Delta has launched a fall bonus miles promotion allowing SkyMiles members to earn double flown miles for flights booked at http://www.delta.com with their American Express cards, then completed during September and October. Mileage awarded will be equivalent to double the actual flown miles, or a total of 1,000 miles for flights less than 500 miles.

To qualify for the offer, members can enroll online now through Oct. 31 at delta.com/falldoublemiles. Members must then purchase a ticket on delta.com using any American Express credit card. Bonus miles will be awarded up to eight weeks after travel is completed.

This offer can bring SkyMiles members a wealth of miles, as three different bonus offers apply. First, members will receive double flown miles during the promotional period. Second, members who purchase with their American Express SkyMiles Credit Card always receive two miles for each dollar spent on Delta Air Lines tickets. And third, all members receive 1,000 bonus miles when purchasing a ticket at delta.com.