Longtime Whole Foods distributor United Natural Foods Inc. (UNFI) reported full-year earnings that exceeded expectations on the bottom line on Wednesday, Sept. 13, just weeks after its most important customer, Whole Foods Market Inc., closed its $13.7 billion sale to Amazon.com Inc. (AMZN)  , also a United Natural Foods customer.

For the year ending July 29, United Natural Foods' net sales were $9.27 billion, up 9.5% year over year, below analysts' expected $9.3 billion. Net income of $2.56 per share exceeded the consensus estimate of $2.55 per share.

In fiscal 2018, United Natural Foods expects net sales to reach $9.63 billion to $9.81 billion, with earnings per share to hit $2.97 to $2.77.

United Natural Foods has been Whole Foods' primary distributor for 19 years, and its current contract expires Sept. 28, 2025. Whole Foods accounted for 35% of United Natural Foods' 2016 revenue, by far its largest customer.

"I am really excited about the opportunities I believe this combination brings to UNFI...[which] is well-positioned" to continue serving both companies, United Natural Foods CEO Steven Spinner said on a call with analysts. "Initiatives around e-commerce capabilities will be a major focus of our growth" going forward, he said, with Amazon and Whole Foods driving United Natural Foods' growth in both the online and brick-and-mortar channels. 

Noting that United Natural Foods filed an 8-K consenting to the merger, Spinner explained that "Whole Foods-Amazon is committed to very specific purchase minimums through the rest of the contract," which was not changed after the deal was announced. 

Disagreeing with Spinner was Ajay Jain, an analyst at Pivotal Research Group LLC, who wrote, "The longer-term implications from Amazon can't be viewed in a favorable light" for United Natural Foods.

Following the close of their merger, Amazon and Whole Foods "emphasized improved merchandising and logistics capabilities which would help to further lower costs for consumers," he wrote. "Over time, we would expect Amazon to streamline Whole Foods' existing supply chain. This could very well include a higher percentage of goods sourced directly from manufacturers," at the expense of United Natural Foods.

Amazon isn't all bad news for United Natural Foods, however. Price cuts at Whole Foods since the close have increased foot traffic, a bright spot Jain added could be offset if Amazon demands concessions from United Natural Foods or sources itself directly from vendors.

While Spinner wouldn't comment on United Natural Foods potentially being obsolete, he touted the company's significant scale "across a lot of products and a lot of suppliers that, quite frankly, is very hard to replicate."

The close of the Whole Foods sale came a year after United Natural Foods lost another major customer, Albertsons Cos., which terminated its United Natural Foods contract months early. Albertsons contributed $410 million to United Natural Foods' revenue.

Customer losses are dangerous for United Natural Foods, which operates in an industry with high fixed costs and high operating leverage, Jain noted.

United Natural Foods shares rose 6.7% to $39.70 in after-hours trading Wednesday.

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