The iPhone 6 from Apple Inc. (NASDAQ:AAPL) should be official in about two weeks. Its impending arrival is evident in that many carriers and retailers are beginning to discount older iPhone models to clear out old inventory and make room for the new model.

T-Mobile US Inc. (NYSE:TMUS) is the most recent carrier to drop its iPhone prices. Starting Wednesday, the network is taking $50 off iPhone models. A T-Mobile retail associate confirmed to International Business Times that customers have to pay for the full price of the Apple handset up front to receive the discount. T-Mobile also gives subscribers the option to pay off the value of their handsets in 24-month installments.

The unofficial T-Mobile blog TmoNews says that discounted models include the iPhone 4, 4s, 5, 5c and 5s; however, availability is dependent on the inventory of individual T-Mobile retail stores. Currently, prices on T-Mobile’s website do not reflect the sale. Additionally, only iPhone 5s and 5c models are available online.

Here are T-Mobile's discounted prices for the most recent iPhone models without a contract: 64GB iPhone 5s: $747; 32GB iPhone 5s: $697: 16GB iPhone 5s: $598; 32GB iPhone 5c: $598: 16GB iPhone 5c: $529

At Sprint Corp. (NYSE: S), customers can get the 16GB iPhone 5c or the 8GB iPhone 4s for free with a two-year contract. The 16GB iPhone 5s is currently $149.99 and the 64GB iPhone 5 is $199.99. Many of Sprint’s deals are Web-exclusives, meaning customers can only receive the discount if they purchase online.

At Verizon Communications (NYSE: VZ), select iPhone models are selling at a 50 percent discount with a two-year contract. The 16GB iPhone 5c is $49.99, the 16GB iPhone 5s for $99.99, the 32GB iPhone 5s is $149.99 and the 64GB iPhone 5s is $199.99. Verizon is also offering the 8GB iPhone 4s for free with a two-year contract.

At Walmart (NYSE: WMT), the 16GB iPhone 5c is just 97 cents with a two-year contract, while the 16GB iPhone 5s is $79. At Costco (NASDAQ:COST), the 16GB iPhone 5s for Verizon and Sprint is $57.99 with a two-year contract, while the 16GB iPhone 5s for AT&T (NYSE: T) is $77.99. At Staples Inc. (NASDAQ: SPLS), the 16GB iPhone 5s is $149.99 with a two-year contract on Verizon and AT&T.

At Target Corp. (NYSE: TGT) the 16GB iPhone 5s is $99.99 with a two-year contract on Verizon, Sprint and AT&T while the 16GB iPhone 5c is $29.99 on these carriers. Target’s deals are only redeemable in stores. At Best Buy (NYSE:BBY) and Radio Shack (NYSE:RSH), many of the iPhone prices reflect the sales prices on the carriers, like Sprint and Verizon.