Don't just have the card linked, need to also be enrolled in using AMEX Membership points on Amazon. You can do that in the settings. This might help those getting its not available to you.
Those with American Express cards linked to their Amazon account and are eligible for this offer, spend at least .01 cent of your rewards balance with an order and receive an extra 20% up to $100 per member. Order must be fully paid with the eligible American Express card.
- 1 - Click the button below to activate this offer on your account. This credit will stay active on your account until the promotion expires or the maximum discount of $50 per customer is redeemed.
- 2 - Add one or more eligible products sold and shipped by Amazon.com to your cart. Look for "sold by Amazon.com" or "sold by Amazon Digital Services LLC" on the product detail page.
- 3 - Check out with your American Express Card and use Membership Rewards points for at least a portion of your order. Learn more about applying Membership Rewards points here.
- 4 - Come back to Amazon.com and get 20% off your purchases when you shop with Membership Rewards points. No need to reactive this credit on your next order, savings will be reflected at checkout.
July 12th edit: Thanks for bringing this back! Funny as I participated and then remembered I had posted this originally to come back and see it bumped.
This order included 8 pre-order games and 1 order of $17 worth of clothes.
Item subtotal: $496.77
Shipping & Handling: $0
Prime Savings: -$83.89
Amex 20% off: -$99.35
Total before tax: $313.53
Estimated tax: $24.29
Reward Points: -$0.01
Grand Total: $337.81
First game, Octopath Traveler just shipped for $39.20 after tax.