Amazon’s Prime program includes third-party merchants, whose shops let the online Everything Store expand its inventory without building more warehouse space. While the company is experimenting with making these merchants part of the Prime program for items that already have free shipping, However, some of these merchants get to limit how far they will ship an item for free.

This is logical for smaller companies that don’t have the same bargaining power with the U.S. Postal Service and private carriers as Amazon, and who simply don’t want to subsidize cross-country two-day shipping. The Wall Street Journal reports that sellers can define which geographic regions they’re willing to provide free Prime shipping for, and customers in other areas pay standard shipping fees.

Another Amazon shipping experiment that the WSJ learned about from an unnamed source is called “Amazon Day,” a service that would combine all of a household’s Amazon orders on the same day of the week. This would cut back on shipping costs for Amazon, which doesn’t really want to send multiple items in multiple packages to the same Prime-addicted house.

The Amazon Day (not to be confused with Prime Day) idea is still being “studied” though, and not in the testing phase yet.

In New Amazon Prime Program, Not All Goods Ship for Free [Wall Street Journal]

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