Those on the hunt for a bargain smartphone will often turn to eBay for a secondhand device or unwanted present that someone is selling at a knockdown price. Now, eBay wants you to buy a prepaid wireless plan at the same time.

The ecommerce giant has partnered with mobile virtual network operator (MVNO) Red Pocket Mobile in the U.S. to cross-sell phone buyers a SIM card and plan as they hit the checkout.

Choose your plan

With Apple’s new iPhones now out in the wild, there will likely be a flurry of people looking to offload their old iPhones to make way for their shiny new device. And if you go hunting on eBay for one of them, you’ll now see a little box at the bottom inviting you to sign up for a 30-day Unlimited wireless plan courtesy of Red Pocket for $29.

Above: eBay: Phone listing with wireless plan

On the next screen you can actually upgrade to a 360-day plan, with various options available.

Above: eBay wireless plan: Take your pick

For Red Pocket Mobile, this deal is a no-brainer in terms of elevating it above the myriad other MVNO players out there — eBay is among the world’s biggest marketplaces for buying and selling phones, with one sold every four seconds in the U.S. alone.

For eBay, this offers a lucrative inroad into the mobile phone plan realm, where it will presumably get a cut of all sales Red Pocket receives. The reason it chose Red Pocket Mobile was that the MVNO actually lets subscribers choose any of the major networks they want to use, a key factor given that coverage varies depending on where you are in the country.

“Red Pocket Mobile is the natural partner for us to launch our add-on wireless plan,” noted eBay category manager David Grim. “Because Red Pocket works on all of America’s major networks, their service can apply to virtually all of the millions of phones sold on eBay.”

It’s perhaps also worth drawing a comparison here with FreedomPop, a well-funded MVNO that offers SIM cards with completely free basic mobile service plans. A couple of years back, FreedomPop shook off its wireless plan roots and took on eBay with its own online store for refurbished smartphones. So it’s interesting to see eBay move in the opposite direction by selling MVNO wireless plans.