Originally Posted by
sacha728
Your free bag on Delta is only when you book on Delta with your Delta Amex card. You will not get the free bag is you book on Expedia, not even is you book on the KLM or Air France site. It does not matter who operates the flight, as long as the flight has a code share for delta, you won't be charged.
I know this is a first time post, but huh? You don't need to book the ticket with your DL Amex card (some other carriers do require you to pay using their co-brand card to get the baggage benefit), you just need to be on a "Delta operated" flight and have your SkyMiles number linked, and you're set. Nothing else you mentioned matters. If you flying on a Delta airplane with your SkyMiles number attached, then you will get the first checked bag included.