Amazon Prime to offer free same-day delivery

5 stunning stats on Amazon
5 stunning stats on Amazon

If you're an Amazon Prime member, your delivery time may be getting shorter. In fact, it may in just a few hours.

Amazon will begin offering free same-day delivery in some metro areas to customers who subscribe to its $99 per year Prime service. Previously, Prime members in those cities had to pay $5.99 per order.

Same-day delivery is already available in 12 metro areas and will now expand to the San Diego and Tampa Bay areas.

Amazon increased spending on its fulfillment centers by almost 20 percent in the most recent quarter.

Related: FAA allows Amazon to test drones in U.S.

The company guarantees a 9 p.m. delivery on orders placed before noon, and will use third-party couriers to offer delivery seven days a week. Amazon would not disclose the number of delivery companies that it works with because, a spokesman said, its delivery methods are part of the company's "secret sauce" that's made it so successful.

Amazon (AMZN) said the number of products available for same-day delivery will continue to expand in the coming months, but more than a million products -- including electronics, books, travel equipment and school supplies -- are already available. Amazon also rolled out on-demand food delivery last week in Manhattan.

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