Holiday shopping? Buy this: Analyst

If you've yet to complete your holiday shopping list, you're not alone. Last-minute shopping is all the rage, and express delivery service workers are breaking a sweat.

The National Retail Federation released the results of its last consumer spending survey for this holiday season, on Wednesday. The report shows 90 percent of holiday shoppers have yet to complete their shopping lists.

Don't fret, this analyst says it really pays off to shop last minute. While retailers always plan to sell some items cheaper, the sales get better as retailers find more left on the shelves than they expected.

"Unplanned [markdowns] are the ones where the stores are getting desperate, in a nutshell: apparel" said Mary Epner, principal retail analyst at Mary Epner Retail Analysis. "There are a few brands in particularly that are very hard hit."

Talking to CNBC's "Power Lunch" on Monda, Epner said the best deals in apparel and handbags come from retailers such as Ralph Lauren and Michael Kors.

In the same vein, she noted that fashion and costume watches from last year are also deeply discounted these days, as companies like Timex and Fossil lack innovation that attracts buyers.

"There's not a lot of newness in the costume-watch business," she said. "If there isn't newness, there's no reason to buy."

Retailers continue to battle over speedy and controlled delivery.

"I think Amazon is starting to take some steps where they're going to do a better job of getting products to customers quicker and have more control over it," said Charles O'Shea, senior analyst at Moody's, on Monday.

While some companies like Amazon rely on third parties to deliver packages, other retailers such as Wal-Mart, Best Buy, and Target offer both online services and in-store pick-up, O'Shea said.