Is Amazon Approaching Peak Prime Membership?

It's common logic that at some point every Amazon.com, Inc. AMZN consumer that plans on purchasing a Prime membership has already done so. In fact, this event may be coming sooner than expected, at least according to Gadfly's Shelly Banjo.

According to Banjo, more than 65 million Americans are members of Amazon Prime, or more than half of all Amazon customers. When accounting for married couples and families that share one Prime membership, the figure is even higher.

Investors should now brace themselves for a slowdown in Prime subscriber growth, although this may already be happening as Amazon is looking to boost its membership by offering monthly subscriptions for $10.99 instead of forcing consumers to pay an annual fee upfront.

Nevertheless, achieving peak Prime membership is something that was bound to occur. Apple Inc. AAPL experienced more than a decade of strong year-over-year growth until the inevitable happened -- everyone who wants an iPhone already has one.

Banjo noted that reaching peak Prime in of itself isn't necessary a problem. Prime members do spend twice as much as non-members and Amazon continues to expand into new categories including apparel, streaming music services and even food to push consumers to spend more in its ecosystem.