Starting Tuesday, Amazon.com Inc. (NASDAQ: AMZN) will offer one- and two-hour grocery delivery to local Prime members for no additional cost in hopes of tapping into a quickly expanding niche.

Those paying for the $119-a-year Prime subscription previously had to fork over an additional $14.99 per month for the same-day grocery service, Amazon Fresh. Along with D.C., this service will be available to the roughly 2,000 cities and towns where Amazon delivery already occurs.

“Grocery delivery is one of the fastest growing businesses at Amazon, and we think this will be one of the most-loved Prime benefits,” said Stephenie Landry, vice president of grocery delivery, in a statement provided to the Washington Business Journal.

The move will certainly cost the company more. And while Amazon's shipping expenses are rapidly growing, revenue from Amazon's monthly subscription services has seen slower gains. 

> Click/tap here to read more at the Denver Business Journal.

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