One of the biggest shopping days of the year is the last Saturday before Christmas, also known as Super Saturday. With many Americans free to shop all day, it will be a productive day for retailers.

Based on its annual survey conducted along with Prosper Insights & Analytics, the National Retail Federation (NRF) estimates that 147.8 million U.S. consumers will participate, up from 134.3 million last year. That number includes both in-store and online activity.

“While many people started holiday shopping early, those who waited until Thanksgiving weekend are feeling the pressure due to the limited number of days this year between Thanksgiving and Christmas,” says NRF President and CEO Matthew Shay. “But there is still time to catch up. The last Saturday before Christmas has become the biggest shopping day of the year, and we expect an impressive turnout by procrastinators and those who just want to take advantage of really good deals.”

Despite the holiday shopping season starting earlier than ever, many still put off getting their final holiday gifts until the last few days. NRF’s survey found that more than half (56 percent) of holiday shoppers plan to purchase their last gift during the week before Christmas, and 62 percent are expected to shop on Super Saturday.

“Most of us are guilty of having that one last gift we need to buy,” says Prosper Executive Vice President of Strategy Phil Rist. “Men and younger consumers continue to be the biggest procrastinators and are expected to turn out in force on Super Saturday.”