Amazon is starting to offer even faster same-day shipping in select cities. The company has built out new warehouses in Dallas, Orlando, Philadelphia, and Phoenix that allow it to deliver orders in a matter of hours, whereas it previously couldn’t guarantee delivery until the end of the day.

Normally, Amazon’s same-day shipping requires customers to place an order by around noon, and the delivery may not arrive until as late as 9PM. In these four cities, customers can now place an order as late as 5PM and still receive their order the same day, and their deliveries are estimated to come sooner. Orders placed overnight should arrive by 1PM; orders placed in the morning will come by 6PM; afternoon orders should come by 10PM; and evening orders are supposed to arrive by 8AM the next morning.

Amazon says it’s able to do this thanks to new “mini-fulfillment centers” it built in these cities. Like before, only certain items stocked inside these warehouses are eligible; Amazon told Reuters they’ll stock around 100,000 products. These facilities are supposed to be about one-tenth the size of a traditional Amazon warehouse and located closer to the cities.

Oddly enough, this is not the only same-day shipping service Amazon offers. Amazon also offers Prime Now, which offers two-hour delivery on “thousands” of items. Amazon Fresh, the company’s grocery delivery service, offers two-hour delivery, too. This new program will even rely on the same delivery service, which uses contractors to pick up orders and drive them to customers.

Amazon has taken heat lately for its contributions to climate change, and the company goes out of its way to address the issue in its blog post announcing this new program. Amazon says that “while it may seem counterintuitive,” this program helps to lower the company’s carbon footprint by reducing the distance drivers have to travel to customers. (The company has also since responded to employee protests with a climate pledge; Amazon founder Jeff Bezos later committed $10 billion to fight climate change.)

The faster same-day shipping option is free to Prime members on orders over $35, or it’s $3 extra for less expensive orders. You can also pay $13 per order if you don’t have a Prime subscription. Amazon will add more cities later this year, the company told Reuters.

Correction March 3rd, 2:53PM ET: The cost of faster same-day shipping for customers without Prime subscriptions is $13 per order, not $10 as initially stated. Amazon states on its website that the cost is $10 per order, but a spokesperson tells The Verge that the lower price only applies to “regular” same-day shipping, not the “faster” same-day shipping described in this article. This story has also been updated to say that the new program relies on Amazon’s contract delivery service.