Six Argo Tea locations in Chicago will go cashless Monday, a sign of the growing influence of plastic and mobile ordering at restaurants and retail stores.

The Chicago-based chain will stop accepting cash at its cafe in the Loop and those at the University of Illinois at Chicago, the Merchandise Mart and three locations at O’Hare International Airport.

Argo said the introduction of cashless cafes will allow it to speed up service. It has 16 Chicago-area locations, according to its website. It didn’t say why these locations were chosen, but they are in some of the most trafficked places in the city, making speed of service critical. It also didn’t say what percentage of sales are cash transactions.

Argo is encouraging customers to use mobile payment options more often by offering a $5 credit when they download the company’s app.

As an alternative for those customers who don’t want to use their smartphones, credit or debit cards, Argo said it is working to develop an in-store gift card kiosk that will accept cash.

In addition to increasing service speeds, banning cash also allows a retailer to collect more data on its customers’ buying habits. It’s also considered safer, since cash won’t be available in the register, deterring possible thefts.

The trend toward banning cash has been slow so far in Chicago, but some retailers and restaurant chains have tried it. Sweetgreen, a salad chain that opened in Chicago last year, is now cashless at all of its locations. Clothing retailer Kit and Ace, which has a store in the Fulton Market district, has never taken cash, saying it allows stores to be more efficient.

For Argo, especially in the locations it chose, going cashless doesn’t run a significant risk of angering customers, said John Gordon, principal at Pacific Management Consulting Group. Restaurants and coffee shops in city centers tend to see the least cash sales, Gordon said. And brands like Argo and Starbucks tend to see fewer cash sales than brands like Dunkin’ Donuts or McDonald’s because they cater to a more affluent customer.

There’s an added benefit of going cashless, as well: People tend to spend more when they pay with their phones or credit cards.

“Will it turn off some customers? You bet. But I’m guessing there is a significant upside,” Gordon said.

Gordon believes that the cashless trend is still in its very early stages, but he expects big restaurant and retail brands could follow in five to 10 years.

Lauren Zumbach contributed.

sbomkamp@chicagotribune.com

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