The specific deals will vary from retailer to retailer, with some offering free expedited delivery without restriction or based on a particular dollar amount spent. The necessary coupon codes will be posted on the Web site on the 17^th at around midnight.   

Knowles said that at least half of the deals will include free shipping on all orders regardless of the amount. “This year we are encouraging merchants to offer blanket free shipping and are giving those that do better placement on the site,” he said.

Last year, www.freeshippingday.com drew more than 250,000 unique visitors in the ten days leading up to Free Shipping Day including more than 100,000 on the day itself.

“One of the stories that is rarely told about Free Shipping Day is how it helps small online business owners," Knowles said. "Any merchant is allowed to participate so long as they offer free shipping with delivery by Christmas Eve, and we don't give better placement because a retailer might be more well known. This has lead to a lot of exposure that small businesses would never have received before.”

A key reason the promotion has taken off is because it encourages consumers to keep shopping closer to Christmas. Historically, online purchases drop dramatically after Dec. 12, Knowles said. While Knowles does not charge merchants to take part in Free Shipping Day, he acknowledged an affiliate relationship with about 20 percent of them, a relationship that compensates him for driving traffic to to those merchant sites and gives him a small percentage of each sale.

For more on holiday shipping and deadlines, click here.