Pick a survey, any survey, about e-commerce delivery and there is one constant: Free shipping matters to consumers.

When Internet Retailer surveyed consumers in late December about what matters to them when shopping online, 52.8% said free shipping was most important, 9.4% said fast shipping was their primary concern and 37.8% said free and fast shipping are equally important. The survey of 510 U.S. consumers was conducted by digital insights firm Toluna.

And, when given a choice between just free shipping or fast shipping, 88% of consumers selected free and 12% chose fast, according to a Deloitte LLP survey of 5,085 U.S. consumers conducted in September.

“Free is always good,” says Fiona Dias, principal digital partner at Ryan Retail Consulting and former chief strategy officer at ShopRunner Inc., which aims to help retailers compete against Amazon.com Inc. by offering an annual or monthly membership that includes unlimited two-day shipping on items purchased from hundreds of online retailers, including Brooks Brothers and Fanatics in its network. When it comes to e-commerce fulfillment and shipping, the bar continues to rise as consumers’ expectations climb higher, she says. That shift is due to the growing number of consumers—estimated by Consumer Intelligence Research Partners at 90 million in the United States as of Sept. 30—who are Amazon Prime customers who pay for free two-day (and sometimes faster) shipping as part of their annual or monthly membership, as well as the faster shipping times offered by many other e-retailers, she says.

“When I started in this business 20 years ago, fast delivery was 14 days. Then every year it would change …

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