America’s largest employer is now working with America’s largest social network.

Walmart has signed on as a new customer for Workplace, the enterprise version of Facebook’s social network specifically for interoffice communication.

Facebook won’t say exactly how many of Walmart’s 2.3 million employees are using the Workplace service, but confirmed that it is Facebook’s largest Workplace deployment in the U.S., which means there are more Walmart employees with access to the product than any of Facebook’s other customers. (Again, though, this doesn’t necessarily mean that all those with access are using it.)

Walmart is not yet paying for Workplace — Facebook offers a 90-day free trial of the product — but will be a paying customer once the free trial is over, according to a Facebook spokesperson.

Workplace doesn’t make a lot of headlines, but the company claims it’s growing. Workplace has 14,000 companies using the product, including Starbucks, Spotify and Lyft; when Workplace officially launched last October, Facebook had just over 1,000 companies on board.

The Walmart news is a reminder that Facebook’s business is beginning to expand beyond digital advertising, where it makes the vast, vast majority of its revenue. Facebook doesn’t break out revenue for Workplace, but the product is ads-free; the company makes money by charging a monthly subscription fee.

—By Kurt Wagner, Recode.net.

CNBC’s parent NBCUniversal is an investor in Recode’s parent Vox, and the companies have a content-sharing arrangement.

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Source: Tech CNBC
Walmart is using a free trial version of Facebook's Slack competitor