Just as Delta has with Porsche and American with Cadillac, United has a relationship with Mercedes.

Sales site TrueCar is back offering lots of United miles again for Mercedes car purchases.

Last year there was an offer for elite members only to receive miles for new cars.

This time the offer is open to all MileagePlus members, and is for used Mercedes vehicles.

In order to be eligible for the offer you either need to have been a MileagePlus member for six months or have credited a flight to your account. They seem to be afraid of people gaming them, perhaps who were going to buy a Mercedes anyway and weren’t even MileagePlus members before walking into the dealership. Perhaps the concern is that Mercedes’ own sales staff will be the ones gaming the system (creating new accounts they control, in the most nefarious version, or using this unnecessarily as a sweetener to close a sale).

To take advantage of the offer, print out a Savings Certificate to present to the dealer. You can only earn miles through this offer once per calendar year.

Oddly, when you log into the site with your MileagePlus number, the offer is presented correctly as 25,000 miles for a used Mercedes. And I’ve tested – non-elite accounts may log into. However, the terms and conditions presented on that page appear to be from an older offer from a year ago aimed at elites for the purchase of a new Mercedes: They begin,

The bonus mileage offer and incentives on select new Mercedes-Benz vehicles are only available to members who are U.S. residents are MileagePlus Premier members at the time of an eligible transaction.

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