Instacart said customers in more than 300 store locations in 15 of the largest cities in the U.S., including Chicago, Los Angeles, Miami, San Diego, San Francisco, and Seattle, will now be able to access 30-minute delivery from dozens of beloved grocers and specialty retailers in their area, including Ralphs, Safeway, Sprouts Farmers Market and Stater Bros.

Following the initial launch, Instacart plans to bring 30-minute delivery to more stores in more cities in the coming months. Instacart is also expanding 45-minute and 60-minute delivery for more customers in more cities nationwide as part of the Priority Delivery launch, making the weekly grocery shop faster than ever before.

“We know that no two grocery shops are created equal — whether it’s a bulk buy for the week ahead or just a few ingredients for tonight’s dinner — so we’re launching new features that support the many ways people shop for their groceries today,” Instacart vice president of product Daniel Danker said. “For many customers, every minute counts when they’re in a pinch and need something in a hurry. With today’s launch of Priority Delivery, we’re redefining the ‘quick run to the store’ and bringing the grocery express lane online for customers.”

The Priority Delivery service is part of Instacart’s effort to make it easier for customers to shop from the Instacart marketplace and discover their favorite retailers and fastest delivery windows available in their area. Priority Delivery gives customers a real-time view of the fastest available delivery windows — indicated by a new lightning bolt icon — enabling customers to shop based on what they need, when they want it, and where they want to shop, the company said.