What is an Unlocked iPhone? Why do I need one?

Last Update: 1/1/2021

What is an Unlocked iPhone?

Unlocked Smartphones like an Unlocked iPhone allow you to use the phone on any cellular network (provided it is wireless compatible), you are no longer locked to a single carrier or stuck in a 2 year contract! An unlocked smartphone is a phone that is not tied to a specific carrier or contract. Freedom! You can sign up for low cost no contract cell phone plans from $30 a month.

eBay Daily Deals are a good source of unlocked iPhones.

If you travel overseas, an unlocked phone is a MUST. With an unlocked phone, you'll pay the same lower rate as the locals do for calls in that country. It can be as easy as purchasing an unlocked phone in the U.S., traveling to your destination country and purchasing a local SIM card.

Be sure to also read How to use your Smartphone Overseas.

Why Buy an Unlocked Smartphone?

There is a lot of trouble involved in finding the right unlocked and compatible Smartphone. Why do some people go through these troubles?

• Carrier Flexibility – Switch Carriers at any time without being locked in
• No contracts – Use a prepaid service provider, with no monthly commitment
• Travel – Use your Smartphone internationally and without huge roaming bills
• Variety – Use phones that aren’t available in the US
• Early Adopter – People who want the latest Smartphone
• Replacing broken phone – Just pop the SIM card into a new phone

Unlocked Smartphones are not that popular in the US. Amazon, eBay, and Newegg have some unlocked phones. You can also pay full price for a Smartphone from most carriers and also Apple, to get an unlocked phone.

Being tied to 1 carrier also limits your selection of phones. The major carriers do not sell every make and model of phone.  You have a world of new phones to choose from when you go the unlocked route. Phones under $100, the latest phones $650+, and everything in between.

Most Smartphones that are purchased from the major cell phone carriers in the US (AT&T, Sprint, T-Mobile, and Verizon) are sold at a steep discount, but tied to a long term contract. A state of the art phone will sell for $199 with a 2 year commitment, full price with a monthly installment payment, or can be purchased outright for around $649 without the carrier subsidy.

The carriers that sell the discounted smartphones, lock the phones so that they only work on their network. Only after you have fulfilled your contractual obligations, (usually two years), will they unlock your phone so you can use it with another company.

Unlocking your iPhone

AT&T and Sprint iPhones are not unlocked even if you pay full price, so we would stick to an Apple sold Unlocked phone instead. Verizon phones are unlocked if purchased at full price. T-Mobile iPhones are unlocked if purchased at full price directly from Apple (as opposed to from T-Mobile.)

Effective 2/12/2015, all cellphone carriers are required by the Government, to unlock your phone once you have fulfilled applicable postpaid service contract, device financing plan, or payment of applicable early termination fee. Prepaid cell phones can be unlocked one year after being activated. They must unlock cell phones for military personnel.

Specific Unlock policies: AT&T - Verizon - T-Mobile - Sprint

Some enterprising cell phone service centers can unlock factory locked iPhones for a small fee, but these technique does not work on all iPhones. There is always the possibility bricking or making a phone no longer function if you unlock a phone by hacking it. Doing this will probably void the warranty. When you purchase an unlocked Smartphone, you need to determine who unlocked the phone. The best ones were unlocked at the factory or were unlocked by the carrier.

Verizon Standard 2 Year Contract for iPhone 7

We will list out the charges due when you sign up for a Typical 24 month installment plan for two of the most popular Smartphones on Verizon Wireless. You can compare this to the cost of an unlocked iPhone 7.

iPhone 7 32GB with Edge Plan. This allows us to upgrade after one year.

Amount due at sale:

$20 Activation fee (Sometimes it is waived when buying online)

$0 for the Smartphone (It does go on sale from time to time)

Sales tax on full value of phone $57 in our area.

Total due at time of sale: $0 + $57 Sales Tax + $20 activation fee = $77.

Monthly Charge $27.08 for 24 month = $649.92.

Monthly Service Plan:

Medium plan 3GB with unlimited talk and text

Smartphone Line Access $20 + $45 3GB Shared Data = $65/month

Total due each month for phone and plan: $92.08 + taxes

Amount Paid to fulfill contract: (24 months)

$92.08 X 24 months = $2209+ $0 + $57 Sales Tax + $20 activation fee = $2286. Price checked June 2016.

iPhone 7 value is now roughly $250 after 2 years

After 2 years your monthly bill would drop to just the service plan as you paid off the phone.

Bringing your own iPhone 7 to Verizon, Monthly Charges

Initial Phone Cost $649.99 + $57 Sales Tax = $706.99.

Monthly Plan:

Medium plan 3GB with unlimited talk and text

Smartphone Line Access $20 + $45 3GB Shared Data = $65/month

Total due each month: $65

You can switch carriers at anytime.

Your monthly costs are the same whether you buy the phone outright or pay for it with installment.

Specifications to Look for in an Unlocked iPhone

You need to ensure that any phone you buy works at full speed on the carrier you wish to use it on.

Cellular Network Compatibility

Because some of the network providers in the USA utilize different cellular network technology, you cannot take an unlocked phone from say, Verizon and make it work on AT&T.

Carrier Name                    Network Technology

AT&T                                   GSM, LTE

Sprint                                  CDMA, LTE

T-Mobile                             GSM, LTE

Verizon                                CDMA, LTE

As you can see from the above chart, each network uses different technology. To make things even more complicated, within a specific network technology, there are different frequencies available. The frequencies a carrier uses are defined by spectrum that they have acquired.

The big spec to watch for is LTE band support.

LTE Bands US Carrier Require

The main LTE band for each carrier is bolded - * indicates optional as of 2016

You need to have almost every band a carrier requires to enable full support and performance of a phone through the entire USA. The frequencies used by a carrier vary from area to area.

• AT&T has Band 30 as optional right now for cities with lots of congestion
• T-Mobile has Band 12 in some areas. It allows better penetration in buildings

As you can see from this table, it is a nightmare trying to make a phone work on multiple US carriers. When purchasing an unlocked Smartphone, you want to make sure it runs on the fastest network possible, so you need to compare the phones specifications with your carrier’s network frequencies.

Confirm that the phone you purchase will work at full speed on the cell phone network you want to join. Sometimes just buying the phone for full price from the carrier, is your safest bet.

Read on for details on these confusing stats.

iPhone 7/7 Plus 6S/6S Plus LTE Band Carrier Compatibility

Each generation of iPhone includes different models that work on different wireless carriers. It is important to understand the differences between each model.

Apple has a useful page summarizing recent iPhone models and compatibility with different worldwide networks. iPhone 6 and older have many more differences between models.

The iPhone for AT&T and T-Mobile does not support CDMA and will not work on Sprint or Verizon Wireless. It will use 3G cellular technology for voice services and either 3G or 4G LTE cellular technology for data services.

If Sprint or Verizon Wireless is your wireless carrier, your iPhone will work on AT&T and T-Mobile once unlocked.

These models sold in the US support these all LTE Bands

• 1, 2, 3, 4, 5, 7, 8
• 12, 13, 17, 18, 19
• 20, 25, 26, 27, 28, 29
• 30, 38, 39
• 40, 41

AT&T Wireless

• iPhone 7 Model A1778
• iPhone 7 Plus Model A1784
• Does not support CDMA

• iPhone 6s Model A1633
• iPhone 6s Plus Model A1634
• Adds support for LTE Band 30 2300Mhz -  This higher-frequency band works better among buildings outdoors, as well as in corporate, convention center, and airport indoor deployments.
• These two models also handle all the LTE networks that A1688, A1687 support.
• Buying an unlocked iPhone 6S/6S Plus will get you these models

This model is sold locked, and is unlocked after it is fully paid for.  If you pay full price, you still have to have an ATT account in good standing for 60 days to unlock it.

T-Mobile

• iPhone 7 Model A1778
• iPhone 7 Plus Model A1784
• Is the same as the AT&T Model
• Does not support CDMA

• iPhone 6s Model A1688
• iPhone 6s Plus Model A1687
• These models are also sold in many countries outside the USA

While the model A1688 and A1687 are also identified as GSM or CDMA, the phones are actually identical. They are just activated for one or the other, but can be used on either kind of network.

Sprint, Verizon Wireless, Apple iPhone Upgrade Program

• iPhone 7 Model A1660
• iPhone 7 Plus Model A1661
• Includes Support for CDMA

• iPhone 6s Model A1688
• iPhone 6s Plus Model A1687
• These models are also sold in many countries outside the USA

While the model A1688 and A1687 are also identified as GSM or CDMA, the phones are actually identical. They are just activated for one or the other, but can be used on either kind of network.

CDMA technology (Used by Sprint and Verizon) doesn’t rely on a SIM card like GSM phones, and carriers have more control over activation. However, all new “CDMA” iPhones include a GSM SIM slot, and have since 2011.

Using USA purchased iPhone 6S / 6S Plus in China

The American iPhone 6S /6S Plus models listed above do work in China, but not in all modes.

• iPhone 6s Model A1633, A1688 works on China Mobile (2G?) and China Unicom 4G. Unicom has a fast HSPA 4G network. Some have gotten it to work on China Mobile in 4G.  LTE does not appear to work. Anyone have more reports?

The Chinese iPhones for use by China Mobile, China Telecom, and China Unicom: Models A1700, A1691, A1699, A1690 lack ATT Band 30. An optional AT&T LTE Band that is used in congested US cities. These models also have special customizations done for China.  iPhone 7 A1660 and iPhone 7 Plus A1661 does include Band 30.

You can use 4G LTE for China Telecom with these Chinese models:

• iPhone 6s (Model A1700)
• iPhone 6s Plus (Model A1699)
• iPhone SE (Model A1723)

iPhone SE model A1723 sold in China will work with China Mobile's 4G TD-LTE, 3G, or TD-SCDMA networks.

Tap Settings > Cellular and turn on Enable 4G.

You cannot use 4G LTE for China Telecom with the following Chinese models:

• iPhone 6s (Model A1691)
• iPhone 6s Plus (Model A1690)
• iPhone SE (Model A1724)

iPhone SE model A1724 sold in China will work with China Mobile's 4G TD-LTE, 3G, or TD-SCDMA networks.

Only unlocked iPhone models purchased in the United States, China, or Japan will work with China Telecom’s SIM card. Details

iPhone 6/6 Plus LTE Band Compatibility

iPhone 6/6 Plus compatibility is not as universal as the 6S / 6S Plus.  There are several models to consider when purchasing.

AT&T Wireless iPhone 6

• iPhone 6 Model A1549 GSM
• iPhone 6 Plus Model A1522 GSM

These models sold in the US support these LTE Bands

• 1, 2, 3, 4, 5, 7, 8
• 13, 17, 18, 19
• 20, 25, 26, 28, 29

This model is sold locked and is unlocked after it is fully paid for.  If you pay full price, you still have to have an ATT account in good standing for 60 days to unlock it.  It does not support CDMA networks of Verizon or Sprint.  The Sprint or Verizon versions support more LTE frequencies.

Sprint iPhone 6

• iPhone 6 Model A1586 CDMA
• iPhone 6 Plus Model A1524 CDMA

These models sold in the US support these LTE Bands

• 1, 2, 3, 4, 5, 7, 8
• 13, 17, 18, 19
• 20, 25, 26, 28, 29
• 38, 39
• 40, 41

Several more frequencies that the other iPhone 6 models. It is sold in many other countries. Sprint iPhone 6 is sold locked to Sprint, and needs to be unlocked for international use. Can't be domestically unlocked by Sprint.

T-Mobile iPhone 6

• iPhone 6 Model A1549 GSM
• iPhone 6 Plus Model A1522 GSM

This model is sold unlocked and without a contract. It does not support CDMA networks of Verizon or Sprint.  The Sprint or Verizon versions support more LTE frequencies.

These models sold in the US support these LTE Bands

• 1, 2, 3, 4, 5, 7, 8
• 13, 17, 18, 19
• 20, 25, 26, 28, 29

Verizon Wireless iPhone 6

• iPhone 6 Model A1549 CDMA
• iPhone 6 Plus Model A1522 CDMA

These are the most versatile iPhone 6/6 Plus. Similar to AT&T's A1549, A1522 but adds support for CDMA EV-DO Rev. A and Rev. B (with 800, 1700/2100, 1900 and 2100 MHz bands. All Verizon iPhones are factory unlocked.

These models sold in the US support these LTE Bands

• 1, 2, 3, 4, 5, 7, 8
• 13, 17, 18, 19
• 20, 25, 26, 28, 29

Unlocked iPhone 6 / 6 Plus sim-free Outside USA

• iPhone 6 Model A1586 GSM
• iPhone 6 Plus Model A1524 GSM

An unlocked version of the Sprint iPhone. Many frequencies are supported both GSM and CDMA. Sold unlocked outside the USA. Supports CDMA EV-DO Rev. A and Rev. B (800, 1700/2100, 1900, 2100 MHz)

Sim-Free means that it is carrier unlocked and does not include a SIM card.

These models sold in the US support these LTE Bands

• 1, 2, 3, 4, 5, 7, 8
• 13, 17, 18, 19
• 20, 25, 26, 28, 29
• 38, 39
• 40, 41

Using USA purchased iPhone 6 / 6 Plus in China

The American iPhone 6 /6 Plus models listed above do work in China, but not in all modes.

• iPhone 6 Model XXX works on China Mobile (2G?) and China Unicom 4G. Unicom has a fast HSPA 4G network. Some have gotten it to work on China Mobile in 4G.  LTE does not appear to work. Anyone have more reports?

Chinese iPhones for use by China Mobile, China Telecom, and China Unicom: Models A1586, A1589, A1524, A1593 These models also have special customizations done for China. It appears that even though they have the model number as other iPhones, they are customized.

You can use 4G LTE for China Telecom or China Unicom with these Chinese models:

• iPhone 6 (Model A1586)
• iPhone 6 Plus (Model A1524)

These iPhone 6 and iPhone 6 Plus models sold by China Unicom and China Telecom will work with China Mobile's 4G TD-LTE, 3G, or TD-SCDMA networks.

Tap Settings > Cellular and turn on Enable 4G.

You cannot use 4G LTE for China Telecom or China Unicom with the following Chinese models:

• iPhone 6 (Model A1589)
• iPhone 6 Plus (Model A1593)

These two iPhone 6 and iPhone 6 models sold by China Mobile are certified for their 4G TD-LTE, 3G, or TD-SCDMA networks

3G/4G GSM Network Compatibility - Frequency Bands

Unlocked GSM phones use a small SIM card to define which provider a phone will use. Each carrier has its own SIM card. You would expect that you could take a SIM card from say AT&T and just plug it into a T-Mobile phone, but this will not always work.

AT&T and T-Mobile both use GSM technology, so you might expect unlocked Smartphones compatible with one network to work on the others, but the problem is that they each support different frequencies.

Carrier                                  GSM Frequencies

AT&T                                     850/1900Mhz

T-Mobile                              1700/2100 (AWS)/1900 (refarm)

T-Mobile 1900Mhz only works in certain areas, mostly larger cities. Details

Some Smartphones support all the frequencies listed above. These are typically called quad-band cell phones or world phones. If you try to use a phone that does not support a frequency that the carrier requires, it will not work. When purchasing an unlocked phone, it is important to verify the frequencies it supports are compatible with the cellular network you intend to use it on.

Maximum performance using HSPDA+ (4G) is 42.2 Mbps; HSUPA 5.76 Mbps. Actual speeds are less. PC Mag found these speeds in middle of 2013. (Mbps)

Carrier Name       Down Average        Peak      Upload

AT&T HSPA                4.52                15.57       1.08

T-Mobile HSPA          7.66                15.85       1.18

Verizon 3G                  1.08                2.84         0.74

SIM card Compatibility

GSM Phones contain SIM cards of varying size. Newer, more slim Smartphones created the need for smaller SIM cards. There is the original SIM card, a micro SIM card, and a smaller nano SIM card. It is important you get the right SIM card for your phone. There are some cutting tools that will you to trim a larger SIM card into a smaller one, but you should avoid this whenever possible.

Maximum LTE Download Speed

Maximum theoretical peak performance using LTE is 50 Mbps Upload, 100 Mbps Download. Actual speeds are less. PC Mag found these speeds in middle of 2013. (Mbps)

Carrier Name                Down Average              Peak            Upload

AT&T LTE                               16.02                   58.25            6.64

T-Mobile LTE                          13.11                    36.65            7.43

Verizon LTE                             10.25                  53.38            4.55

Other cell companies that piggyback on networks may reduce your maximum speeds in order to give you cheaper rates. For instance: Cricket Wireless uses the AT&T network but throttles maximum speeds to 8Mbps.

XLTE

In May 2015, Verizon unveiled "XLTE", hyped and advertised as another LTE service capable of delivering faster speeds and better coverage. However, Verizon's XLTE service simply doubles the bandwidth for their LTE network by using the AWS frequencies in the 1700MHZ band (Verizon's LTE network normally runs on 700MHZ).

Many other carriers are also in the process of increasing bandwidth for the LTE networks, and many handset manufacturers are now releasing devices capable of running on XLTE, T-Mobile's new LTE network, and AT&T's LTE network. Keep in mind, however, that older devices will not get to take advantage of the new network, and users hoping to use Sprint's new "Spark" network will have to buy new devices made for Sprint's network.

The only way to take advantage of this additional bandwidth provided by wireless carriers is to buy a phone directly from the carrier.

Examples of smartphones that will support XLTE:

• iPhone 5s/5c/6/6 Plus / 6S / 6S Plus / 7 / 7 Plus

Problems with an Unlocked Smartphone

Let’s say that you found an unlocked Smartphone that is compatible with your carrier of choice. What other problems might occur?

• Internet Access – Calls and text are easy, but sometimes getting data to work is complicated
• Special Features – It is possible that some features like visual voice mail will not work
• Cost – You’ll pay a lot more upfront, because there is  no contract
• Support – You are on your own, Googling is about all you can do to solve problems
• Warranty – Most unlocked phones have short or no warranties

In September 2013, an unlocked Samsung Galaxy S4 costs $600, while the same phone with a 2 year contract costs $149. You could purchase the phone directly from AT&T for $700 without a plan, so you do save some money.

Alternatives

Shoppers should also consider buying a pre-owned Smartphone. eBay, and craigslist have many listed. You do need to make sure the phone works, and has not been banned from the network.  Some people trade in their phones, these phones get refurbished and usually make their way to eBay. Buying from a legitimate refurbisher like Gazelle makes sense. You are given a short warranty and a guarantee the smartphone works on the network.

Conclusion

There are many factors you need to research before you purchase an unlocked iPhone. There are many advantages to buying one, but there are many disadvantages. If you are replacing a broken phone or need a phone for travel, this is a great way to go. If you are trying to buy the latest and greatest phone, you need to ensure that it is 100% compatible with the network you intend to use it on.

You have the freedom to switch phone and carriers whenever you want.

Have you purchased an unlocked iPhone? How is your buying experience? Did the phone work on your carriers’ network?