Amazon is to begin delivering alcohol as part of its Prime Now service.
The company's trialling the sale of wine, beer and spirits to US customers in Seattle to start with from its app.
The alcohol will be delivered in one ($7.99) and two-hour (free) slots.
Amazon Prime offers free two-day delivery on millions of items with the retailer trying out lots of new services, ranging from TV and on-demand video to fast delivery.
Prime Now customers can order using an app available on both iOS and Android devices and orders are shipped from smaller warehouses, or hubs.
An Amazon spokeswoman said the company had already opened two facilities in Seattle and Kirkland, Washington, to handle Prime Now deliveries.
Amazon says it has "tens of millions" of Prime subscribers with analysts estimating they have around 40 million users worldwide.
The company launched Prime Now in New York last year but hasn't had as much success in other markets with its grocery delivery service.
It already sells alcohol on its main website.
It has competition from other delivery firms such as Instacart, which is expanding to the US city of Indianapolis, its 17th location.
The Thirstie app also tracks down alcohol people want and promises to deliver within an hour in major US cities including Los Angeles, Miami, New York City and Austin in Texas.
Other startups, like Postmates, which focuses on meal delivery, also deliver personal care goods and alcohol for customers using a network of couriers.
There are several firms delivering late-night alcohol in the UK, mainly in the London area.