Starbucks on Monday announced an expansion of its delivery service in partnership with Uber Eats, which is now headed to six other major U.S. cities, starting with San Francisco this week. It will then roll out to Boston, Chicago, L.A., New York and Washington, D.C., and is on track to reach one-quarter of U.S. company-operated stores in the weeks ahead, the company says.

Starbucks Delivers, as the service is called, first began as a pilot program in Miami this past fall after a successful launch in China, through a partnership with Alibaba and delivery service Ele.me. After bringing its China-based delivery operation to some 2,000 stores across 30 cities across the country by the end of 2018, Starbucks said it would expand its Uber Eats partnership to bring a similar delivery service to more than 2,000 U.S. stores this year.

Today, customers using Starbucks Delivers are able to place orders through the Uber Eats mobile app on iOS or Android. In the app, they can browse both hot and cold food and beverage items, and track their order’s progress as it arrives. Around 95 percent of the Starbucks menu is available through Uber Eats, and orders can be customized just as in the Starbucks app itself.

There’s a delivery fee of $2.49 per booking on these delivery orders.

Despite the increased cost, Starbucks claims it saw strong demand and repeat business throughout the day during its pilot. The company also believes the partnership is enabling the business to reach new customers who are on Uber Eats, but not necessarily venturing out to its stores, while also serving its existing customer base.

“We know we have untapped customer demand for Starbucks Delivers in the U.S. and starting today, we’re expanding our best-in-class experience to our customers both in and out of our stores,” said Roz Brewer, group president and chief operating officer for Starbucks, in a statement about the launch. “We’re building on key learnings from past delivery pilots and by integrating our ordering technology directly with Uber Eats, we’ve unlocked the ability to bring Starbucks to customers for those times when they’re not able to come to us.”

Starbucks now offers delivery in 11 of its global markets, including Miami and Tokyo. It also offers other delivery initiatives in India, Hong Kong, Singapore, Indonesia, Vietnam, Mexico, Colombia and Chile, as well as China.

The company says it will run other delivery pilots outside the U.S. this year. The first of those efforts is London, which has been chosen to be the first European city to test Starbucks Delivers via Uber Eats. London’s test will begin small with company-operated stores before scaling to licensees, says Starbucks.