Retailers just got slammed with 1.5 million return packages in one day - and it reveals a disturbing reality about the future of holiday shopping

Ross D. Franklin/AP

Returns aplenty.

• Customers returned 1.5 million packages on Dec. 19, UPS estimated.
• It's the first time the peak returns day for the year fell before, rather than after, Christmas.
• Vice president of US marketing at UPS Kathleen Marran told Business Insider that the shift in "National Returns Day" indicates just how comfortable consumers are with returning packages - even though it's a major expense for retailers.

Dec. 19 is slated to be the peak returns day this holiday season. UPS estimated that 1.5 million packages were returned that Wednesday - before Christmas.

UPS said that's the first time peak returns fell before Christmas, rather than in early January after the holidays. A second wave of returns, totaling an estimated 1.3 million parcels, will hit on Jan. 3. These returns are included in the 800 million packages UPS anticipates delivering this holiday season.

Those returns come from purchases made before Black Friday and, to a lesser extent, an earlier Hanukkah.

They're also from people buying gifts for Christmas, weighing their choice, and then deciding that they don't want to give that gift after all, Kathleen Marran, vice president of US marketing at UPS, told Business Insider.

Just last year, online shoppers said returns are the worst part about buying online. But it's clear that, as retailers have made returns easier and often free, customers are getting more comfortable with buying things online, testing them out in real life, then returning them.

As Business Insider Intelligence reported from Optoro data, 86% of consumers have returned a product purchased online in the past year. Fourteen percent have returned products four or more times.

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Perhaps the more reasonable choice would be going to a retailer's physical outpost and seeing the product there, particularly during the time crunch of the holidays. But Marran said retailers have hugely simplified the returns process and boosted people's confidence in buying online.

The 2018 holiday season is expected to see $94 billion in returned goods, according to returns optimization firm Optoro. And, while Marran said many retailers are able to resell or repurpose most returned goods, retailers still have to cover the costs of transporting and sorting returned goods.

That's caused many retailers to hone in on "reverse logistics management programs," Marran said. But the pricey process of returns is key to attracting and retaining online shoppers. Optoro said 79% of consumers check return policies before buying products.

"An easy return policy makes return customers for those retailers," Marran said.