Amazon just fired the latest shot against Walmart in the free-shipping wars

Andriy Blokhin/ShutterstockAmazon is expanding its one-day-shipping program.

Amazon on Monday said it was offering free one-day shipping for more than 10 million items to Prime members across the US.

This means Amazon’s one-day-shipping offering is already much larger than the next-day-shipping program that Walmart launched three weeks ago.

Walmart’s offer, by comparison, will initially be available only on a selection of up to 220,000 items, which will vary regionally based on customers’ ordering habits.

Read more: Walmart launches salvo to blow Amazon out of the water with its own free, next-day delivery

Walmart launched one-day shipping in several cities last month, and it plans to make it available to 75% of US consumers by the end of the year. Walmart said it planned to grow the assortment of items available for next-day shipping over time. To access the free next-day shipping, customers must make a minimum purchase of $US35, but don’t have to pay any membership fees.

Amazon said in April that it would shorten its two-day-shipping promise for Prime customers to one day. Amazon’s Prime program costs $US119 annually but requires no minimum purchase amount.

Amazon hasn’t provided details on what percentage of its customers now have access to free one-day shipping. The company said only that it was available “coast to coast” in more than 10,000 cities and towns.

“We significantly expanded one-day selection and the delivery areas starting in early April and we aren’t done,” Amazon said on its company blog. “We will keep adding more products and expanding our delivery areas to ensure Prime members get their products faster than ever.”

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