Forget Santa's sleigh. Ninety-three percent of retailers kept their shipping promises, getting packages to where they needed to be by the companies' last guaranteed shipping date before Christmas.

That's according to Accenture Strategy's 2018 holiday shipping study, which places orders online to see how well retailers perform during the Christmas rush.

In 2017, 100 percent kept their promises, though retailers were more cautious around Christmas and made the average cut-off date for standard delivery a day earlier than previous holiday seasons, research from Kurt Salmon, part of Accenture Strategy, found. The rate was 92 percent in 2016 and 88 percent in 2015.

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The best retailers this year for standard-shipping orders placed on or after Dec. 20, but still arriving before Christmas, were:

• Amazon Prime – ordered on Dec. 22

• Under Armour, Lululemon Athletica, MM.LaFleur, Coach, L.L.Bean, Nordstrom and Zappos – ordered on Dec. 21

• Dillard’s, Macy’s, Timberland, Sephora, Saks Fifth Avenue and Best Buy – ordered on Dec. 20

The 52 retailers tested this year ranged from traditional big boxes to specialty sellers and online-only merchants.

"Delivering on shipping promises before Christmas is extremely challenging and has huge consequences for those that get it wrong," Steve Osburn, managing director at Kurt Salmon, which is part of Accenture Strategy, said in a statement. "With online sales continuing to rise, retailers have to ensure they are operationally robust to deliver on time, able to change direction at a moment’s notice, and offer flexible delivery alternatives to avoid letting customers down."

Fewer companies had last order promise dates this year in an effort to dodge the possibility of letting customers down, according to Kurt Salmon. One-third – the highest percentage in years – decided to stop making that potentially risky pledge to customers as Christmas loomed and rather focused on last-minute sales and fulfilling orders placed online, but picked up from a brick-and-mortar store.

Also scoring big this holiday season were non-traditional retail channels, the study found: for example, Amazon Prime Now – which promises two-hour delivery and was dropping off packages as late as midnight on Christmas Eve – and buying online and then collecting purchases at a store. Many chains – including Kohl’s, Best Buy, Home Depot and Lowe’s – offered this option late on Christmas Eve.

"As retailer networks become even more complex – with multiple distribution centers and ship from store options driving more and more of the fulfillment – retailers need to have systems in place to ensure that the right shipping method gets used regardless of where the items get picked and shipped," Osburn said.

This year's losers were retailers with delivery dates that cut it too close, because they wound up letting shoppers down, the study concluded. The average cut-off date was Dec. 17, but all companies that failed to get their packages where they needed to be on time used Dec. 19 or a later date as their deadline.

The 2018 holiday season was great for retailers, too, according to the Mastercard SpendingPulse, which calculated it was the best in six years. Sales topped $850 billion due to a 5.1 percent increase over last year's total.

Katie Femia did 90 percent of her holiday shopping online this year and suspects she'll up that to 100 percent in 2019. Among the purchases for the 35 people on her list were video games, wireless earbuds, a watch and beauty products, mostly from Amazon and the Target, Walmart and Best Buy websites.

"I’m very pressed for time," said the 39-year-old freelance writer from South Bend, Indiana. "I don't like battling crowds. This helps keep me focused."

But 2018's online shopping season wasn't completely perfect. Femia cancelled one order, because it wasn't going to arrive on time. And two ornaments purchased as gifts eight days before Christmas still hadn't arrived by the Thursday after the holiday.

"Several online retailers I ordered from I’d give an A," she said. "It’s become a real habit for me to order online, because I’ve not had a bad experience to convince me otherwise."