I just joined Marriott rewards during my stay here at Gettysburg, PA.
I stayed in two other Marriotts (Washington, DC, and Baltimore) in the past week. I booked them through Expedia. Can I add them to my rewards history?
Unfortunately, you can't earn Marriott Rewards points for stays booked through Expedia or other third parties. Here is a link to the Marriott Rewards Terms and Conditions
Note item 2 under General Membership
"There are instances when a stay will not be eligible to earn Points or elite night credit. For example, rooms booked via third party online retailers, like Expedia.com, Travelocity.com, Hotels.com, Booking.com, and Priceline.com, are not eligible."
If you want to earn Marriott Rewards points and elite night credits, the best thing to do in the future is to book directly using Marriott's website.
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