Goodwill and mobile marketplace app OfferUp have announced a new partnership focused on bringing Goodwill’s secondhand inventory to the millions of OfferUp shoppers, for both local pickup and delivery. The deal sees over 100 Goodwill stores listing their inventory in OfferUp in New York, New Jersey, San Francisco, San Mateo and Marin Counties, South Florida, Greater Detroit, San Antonio, and Central and Southern Indiana.

The move brings Goodwill’s pre-owned inventory to a modern mobile e-commerce platform, allowing staff to track sales, and view the real-time flow of products, payments, and data in one interface.

However, it’s not the first time Goodwill has gone online. The organization today runs its own e-commerce site, ShopGoodwill.com, and many of its local stores have a presence on eBay.

Via OfferUp, mobile users will now be able to browse their Goodwill’s local inventory in the app alongside other sellers’ content. New items will be uploaded regularly, and listed under the regional Goodwill handles so customers know they’re buying from Goodwill as opposed to an individual seller. These handles will feature a “Verified Business” badge, as well, and the profiles will include helpful information like the store hours, address, and an “about us” section.

The partnership is powered by OfferUp’s new API, currently in beta testing, and Upright Labs’ Lister software, which handles the inventory uploads to OfferUp.

Goodwill will be responsible for managing its listings, including the product images, shipping, order management, financial reporting, and auditing. It’s largely using OfferUp as another sales channel, instead of relying largely on foot traffic to its brick-and-mortar locations.

Like any other OfferUp user, Goodwill doesn’t have a financial relationship with the mobile marketplace.

If a customer buys a Goodwill item, they can go to their local store and pay with cash with no fee. However, if they choose to have the item shipped, OfferUp charges a 9.9% fee to cover shipping and handling across the 48 contiguous U.S. states. This is the same fee any other seller would pay on OfferUp.

The individual Goodwill stores can choose whether or not to offer shipping, the company also says. Some may opt to ship smaller items, like tech, games, or jewelry, but only allow for local pickup if it’s a larger item, like furniture.

The two organizations had already been testing the system ahead of today’s formal announcement about availability. Though early, several Goodwill locations are reporting positive outcomes.

“We started to list furniture and other items from our stores on OfferUp in January, and the early results have been great. The majority of the items we post on OfferUp sell within 72 hours, and some have sold in as quickly as 10 minutes after being listed on the app,” said Jay Lytle, Vice President and Chief Information Officer, Goodwill of Central & Southern Indiana. “The exposure of our high-quality donations to so many new customers, coupled with the feedback and engagement we’ve experienced on OfferUp, has been tremendous for us,” he added.

“Potential shoppers were unaware of the great inventory that our local stores have for sale,” said Goodwill South Florida CEO David Landsberg, in a related statement. “OfferUp allows us to showcase large, pickup only inventory and increase foot traffic to stores. This also translates into new donors, and helps us fulfill our mission of training and employing people with disabilities and other barriers to work here in South Florida.”

OfferUp says it forged the deals with the individual stores in the supported regions, not at a national level, because Goodwill stores operate independently and because employee bandwidth and resources vary by store.

“Every store is looking to increase foot traffic, along with sales, and the leaders we’ve worked with manage multiple stores in heavily-trafficked markets,” an OfferUp spokesperson explains. “With the OfferUp API and Upright Lab’s Listing Tool, employees can take a picture using a mobile device and instantly upload to OfferUp, so it’s improved the flow of receiving and selling their items,” they added.