The Unlocked iPhone 6S comes in two models for US carriers: A1633 and A1688. There is also model A1700, but it is intended for Chinese carriers so isn’t considered for this article.
This post is part of our Unlocked iPhone Buyers Guide meant to answer all your questions about buying an unlocked iPhone.
This article will help answer the question: Which unlocked iPhone 6S should I buy for my carrier network? We’ll discuss the model differences, carrier compatibility, and help you choose the right iPhone 6S for Verizon, AT&T, T-Mobile, Sprint or your favorite MVNO.
Unlocked iPhone 6S: A1633 vs 1688
Both the A1633 and A1688 work well on any US carrier, including Verizon, AT&T, T-Mobile and Sprint. The A1633 is the most comprehensive model.
The A1688 is for GSM and CDMA, sold as the carrier model for Verizon, T-Mobile and Sprint. There is one band difference that makes the A1633 preferred for AT&T users. The A1633 model supports Band 30 on 2300 Mhz (2.3 Ghz) also known as Wireless Communications Service (WCS). Band 30 is an LTE band sometimes used by AT&T for big cities. The A1688 will work fine on AT&T, just won’t take advantage of band 30.
The Unlocked iPhone 6S A1633 is sold by Apple as the SIM-free model and is typically used by Apple for replacement devices. It is also the preferred model for MVNOs such as Cricket, Ting, US Mobile and others.
Buy Unlocked iPhone 6S
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