If you’re the kind of person who likes keeping track of arbitrary holidays, here’s one more to add to your list: Jan. 5, known as “National Returns Day,” or, “The Day You Send That Horrorshow Of A Sweater Back From The Fiery Chasm From Whence It Came.”

It’s going to be quite a busy day for shipping companies, as UPS says it’s expecting to ship more than 1.3 million packages filled with unwanted holiday items back to retailers: record e-commerce sales are pushing up returns this year and peaking on Thursday, Jan. 5, UPS said in a statement today.

In addition to the million or so packages expected on that day, UPS says it will ship more than 5.8 million packages in the first full week of the new year. These numbers are up from last year, when shoppers returned more than 1 million packages on National Returns Day and five million packages in the first week of January.

According to a UPS study, between 2012 and 2016, online shoppers reported fewer issues paying paying for returns shipping (decreasing from 66% to 50%), paying restocking fees (decreasing from 43% to 27%), and experiencing a delay in receiving credits or refunds (decreasing from 41% to 27%).

“Online shoppers want the same level of choice, control and convenience making their returns as they do making their purchases,” UPS’ chief marketing officer said in the press release.

Retailers are also helping, by improving their returns programs, UPS says, despite the fact that they’re probably none too pleased to have to accept all those unwanted items: according to the National Retail Federation, merchandise returns cost U.S. retailers more than $260 billion in lost sales.

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