Uber, which has been testing the service in some areas, said its new UberRUSH will allow consumers in Chicago, New York and San Francisco to get quick delivery of flowers, burritos or "pretty much anything in minutes."
The new service competes with fast-growing startups like Postmates, and is aimed at helping merchants which lack delivery options to expand their consumer base.
"Businesses that tap into UberRUSH will make getting anything in your city faster, more reliable, and more affordable than picking it up yourself," said a blog post from Jason Droege, head of UberEVERYTHING.
Uber will collect fees of USD 5 to USD 6 for deliveries within one mile (1.6 kilometers), with the aim of getting the goods to consumers within minutes by car or bicycle courier.
The move comes weeks after online giant Amazon began recruiting drivers for on-demand delivery of its products in its hometown of Seattle, Washington, with plans to launch in several other cities soon.
Uber's ridesharing service has made it one of the world's largest startups, operating in dozens of countries, but has faced regulatory hurdles in many areas and protests from established taxi operators.