After launching its carpooling service in both Paris and San Francisco earlier this year, Uber is adding New York to that list. Today, the company said it plans to offer UberPool in New York, a city with a lot of people and a lot of cars, but often not people with cars of their own. UberPool, which launches there early next week, offers a way to share a ride with someone else who ordered an UberX ride along the same route. That promises to trim costs anywhere from 20 to 50 percent, Uber says, as well as cut downtime for drivers who are waiting to pick people up.

"On any given day, the vast majority of UberX trips in NYC have a 'lookalike' trip — a trip that starts near, ends near, and is happening around the same time as another trip," Uber said in a blog post. "Most of these trips transport 1-2 people, leaving 2-3 empty seats. With UberPool we can match those lookalike trips together."

Uber began experimenting with the UberPool idea in San Francisco Bay Area in August, promising up to a 40 percent reduction in fares. It expanded that idea to Paris last month, with a discount in the event that a matching co-rider could not be found.

Uber is not alone in matching up strangers who are open to carpooling, though the feature has attracted the attention of regulators that question its legality. Competitor Lyft (which Uber is in a fierce battle with), as well as Sidecar, launched nearly identical services respectively called Lyft Line and Sidecar Shared Rides in early August, with the same promise of cutting rider costs in half. That immediately brought the ire of the California Public Utilities Commission, which called those services illegal and threatened to shut them down.

Update December 3rd, 2:17PM: Uber now plans to launch the service early next week, instead of Thursday. This post has been updated to reflect that new information.