What to do with your old phone when you upgrade to the iPhone 6

Consumers who plan to upgrade their iPhone to a new model have a dilemma beyond choosing between the iPhone 6 and iPhone 6 Plus — namely, what to do with the old phone?

The options fall into four broad categories: Trade it in at one of the four major carriers, head to Best Buy or another store that buys phones, sell it to one of the firms that specialize in buying old phones or try to sell it themselves using a website like eBay or Craigslist.

The nation's two largest providers, Verizon Wireless and AT&T, are offering similar trade-in deals: Up to $200 for an older iPhone 4 or iPhone 4s and iPhone 5 or iPhone 5c in good condition; and up to $300 for an iPhone 5s.

There are certain conditions that apply to these offers: Verizon's offer is contingent upon a two-year contract and AT&T similarly requires that a transaction take place — either an upgrade, a new line added or a new customer.

The two smaller major carrier are getting even more aggressive, promising to beat any other carrier's offer. As part of its pledge, T-Mobile will match any other carrier's trade-in offer and add $50 on top of it.

Sprint's offer includes offering a free 16 gigabyte iPhone 6 for customers who turn in a used iPhone in good working condition and sign up for a two-year agreement.

The struggling carrier also will buy out the remaining contracts for customers who bring their numbers from another carrier and activate an iPhone 6 or iPhone 6 Plus on the Sprint Simply Unlimited plan. Sprint said it will issue Visa prepaid cards worth up to $350 a line for switchers.

Apple iPhone 5S, iPhone 6 and iPhone 6 Plus
Source: Apple Inc.
Apple iPhone 5S, iPhone 6 and iPhone 6 Plus

Retailer Best Buy is pledging minimum trade-in values for older generations of working iPhones. Starting on Sept. 19, when the devices go on sale, any customer who trades in an old phone to upgrade the device or active a new phone, will receive a minimum of $300 for an iPhone 5s and $125 for an iPhone 4s.

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There are other options, too. Consumers looking for quick cash — or to dispose of old phones in an environmentally friendly — way can seek out the ecoATM.

EcoATM operates about 1,100 kiosks in shopping malls and outside major retailers such as Walmart. The ATM-like device will inspect the phone to determine whether the old phone is in working order, check with police databases to determine if it has been reported stolen and, in case it turns out later to be stolen, it will gather information about the person looking to surrender it, collecting driver's license information, photo and fingerprint.

Assuming the phone and seller pass inspection, ecoATM will dispense cash on the spot. The trade-in values are typically less than what you'd receive from one of the major carriers, which in some cases subsidize the exchange, an ecoATM spokeswoman acknowledged. The consumer can always reject the offer once it is made.

Other used-phone specialists include Web-based Gazelle.com.

Finally, of course, sellers can test the open market, offering up their phones on sellers such as Craigslist or eBay.

By Dawn Chmielewski