What Is an Unlocked Phone: Everything You Need to Know

Mobile Phone

When we want to buy smartphones, we have two options: either unlocked or locked phones. The choice depends on our preferences and budget. Some prefer unlocked phones for them to have the freedom to choose the compatible carrier. Moreover, they will have an option to have two SIM cards from different carriers. With that, they can have a number for work or personal purposes. However, some prefer locked phones for different reasons. An unlocked or locked phone, what’s important is that they can provide the service that we want.

In this article, we will discuss what an unlocked phone is, the differences between locked and unlocked phones, and the pros and cons of having an unlocked phone.


What Is an Unlocked Phone?

What Is An Unlocked Phone?
Photo by Matt Pisoni on Medium


An unlocked phone is a phone that is not exclusively tied or locked to one particular phone carrier. It means that the user can choose the phone carrier that he wants. Moreover, when someone has an unlocked phone, he can have two SIM cards from different networks, and he can change from one network to another. Some do this so that they can have a business SIM card and a personal one. On the other hand, some prefer having different SIMs from different carriers. This is because some carriers do have a reliable signal in a certain location only.


List of Unlockable GSM Phones

  • Nokia 4.2, 32 GB – Black/Pink Sand
  • Samsung Galaxy S10e, 128 GB Prism – Prism Black
  • LG K40, 16 GB
  • Motorola Moto G Power Cell Phone, 64 GB – Smoke Black
  • BLU V5, 32 GB – Twilight/Black
  • BLU V7, 64 GB – Black
  • Samsung Galaxy S10, 128 GB Prism – Black
  • Samsung Galaxy S9 64 GB – Midnight Black
  • TCL 10L, 64 GB – Mariana Blue
  • Sony Xperia 10 Plus, 64 GB – Black
  • BLU V9, 64 GB – Black
  • Motorola Moto E, 32 GB – Midnight Blue
  • Samsung Galaxy Note10, 256 GB – Aura Glow
  • Samsung Galaxy S10+, 128 GB Prism – Black
  • LG K30 2019 LM-X320QMG, 16 GB – Black
  • Samsung Galaxy S10e,128 GB Prism – White/Blue
  • Samsung Galaxy Note10+, 256 GB – Aura Glow
  • Sony Xperia 10, 64 GB – Black
  • Motorola Moto G Stylus Cell Phone, 128 GB – Mystic Indigo
  • Samsung Galaxy Note10+, 256 GB – Aura Black
  • BLU Vivo XI+, 64 GB – Silver
  • LG G8X ThinQ Dual Screen, 128 GB – Black
  • TCL 10 Pro, 128 GB – Ember Gray
  • Samsung Geek Squad Certified Refurbished Galaxy S10e,128 GB Prism – Black
  • LG G8 ThinQ, 128 GB – Aurora Black
  • Sony Xperia 1, 128 GB – Purple
  • Samsung Galaxy Note10+, 256 GB – Aura White
  • CellAllure Fashion C, 16 GB – Aurora Lights/IML (Blue and Purple)
  • Samsung Galaxy A6, 32 GB – Black
  • Google Pixel 4 XL, 64 GB – Just Black


List of Unlockable CDMA Phones

  • Google Pixel 3a XL, 64 GB – Just Black
  • Samsung Galaxy S10, 128 GB Prism – Black
  • Samsung Galaxy S20 5G, 128 GB – Cosmic Gray
  • Motorola Moto z⁴, 128 GB – Flash Gray
  • Samsung Galaxy A20, 32 GB – Black
  • Samsung Galaxy A10e, 32 GB – Black
  • iPhone SE (2nd generation), 64 GB – Black
  • Samsung Galaxy S10e, 128 GB – Prism Black
  • Samsung Galaxy Note10+, 256 GB – Aura Glow
  • Motorola Moto G Power Cell Phone, 64 GB – Smoke Black
  • Samsung Galaxy S10+, 128 GB Prism – Black
  • Samsung Galaxy S10 Lite, 128 GB – Prism Black
  • Motorola Moto G Stylus Cell Phone, 128 GB – Mystic Indigo
  • Samsung Galaxy S20+ 5G, 128 GB – Aura Blue
  • Google Pixel 3a XL, 64 GB – Just Black
  • Samsung Galaxy S9, 64 GB – Midnight Black
  • Samsung Galaxy A50, 64 GB – Black
  • Google Pixel 3a, 64 GB – Just Black
  • Samsung Galaxy Note10, 256 GB – Aura Glow
  • LG Stylo 5 – Aurora Black
  • Motorola Moto One Action, 128 GB – Denim Blue
  • Motorola Moto G7 Play, 32 GB – Deep Indigo
  • Samsung Galaxy Z Flip, 256 GB – Mirror Black
  • iPhone SE (2nd generation), 128 GB – Black
  • LG K30 2019 LM-X320QMG, 16 GB – Black
  • Google Pixel 4 XL, 64 GB – Just Black
  • Samsung Galaxy S20+ 5G, 512 GB – Cosmic Black
  • LG G8X ThinQ Dual Screen, 128 GB – Black
  • Google Pixel 3a, 64 GB – Just Black
  • Motorola Moto G Fast, 32 GB – Pearl White
  • Motorola Moto G7 Power, 32 GB – Marine Blue
  • Google Pixel 4, 64 GB – White
  • LG G8 ThinQ, 128 GB – Aurora Black
  • Samsung Galaxy Fold, 512 GB – Space Silver


Difference Between GSM and CDMA Phones

GSM and CDMA are two hugely important technologies for mobile communication. Both sets of technologies turn data into radio waves, which phones use. However, they differ in the way calls and data transfer takes over the mobile phone networks. Moreover, the technologies behind these two are different and not compatible with each other.

In the US, AT&T and T-Mobile use GSM, while Sprint, Verizon, and US Cellular use CDMA.


What the Acronyms Mean

  • GSM – Global System for Mobile Communication
  • CDMA – Code Division Multiple Access.



GSM is an example of a digital mobile network. It is used for transmitting mobile voice and data for mobile devices. Also, it is the most widely accepted standard for communication globally. GSM uses a variation of TDMA and FDMA. TDMA divides time slots for conversation streams and alternates them in sequence. This sequence is shifting between each conversation in very short intervals.

CDMA is the basis for the CDMA2000 and WCDMA standards for 3G technology. It gives its users full access to the whole range of bands. With that, a lot of users are allowed to connect at any given time. Moreover, its network works by covering digitalized calls over one another. Then, it assigns special codes to modify them. Every call data is encoded with a specific key. Because of that, the voice data remains protected and filtered. It means that only those who are involved in the phone call can receive the data.


Rate Of Data Speed

In GSM, the data speed rate is 42 Mbps in HSPA (3G), while in CDMA, it is 3.6 Mbps.


SIM Cards

GSM handsets use SIM cards to link a particular phone with its network. With that, when changing devices, one just has to take the SIM card and place it to another handset. CDMA handsets don’t need a SIM card because they are handset-based standards. The phone is linked to work on the carrier’s network. However, CDMA carriers use SIM cards but only for LTE networks.



GSM phones can be unlocked and its users can remove their SIM card on their phones and move it to another phone. Also, they can use a SIM card from another carrier using the same mobile phone. On the other hand, CDMA phones that don’t have SIM card slots are tied to their carriers. With that, they can’t be transferred to other networks.



If a user bought a GSM phone, they just have to buy a SIM card and put it in their phone. That way, the phone’s network capabilities will be activated. However, if a user bought a CDMA phone, in able to activate it, they need to call their carrier.


Customer Information

In GSM, the customer information is stored in the SIM card, while on CDMA, it is stored in the handset.


How to Unlock a Phone

How To Unlock A Phone?
Photo by Poonam on Android AppsApk


The process of unlocking a phone is simple. You don’t need to have the technical knowledge to do it. However, the procedures of unlocking phones vary. Some important information must be at hand before unlocking your phone.

  • The account holder’s name and account number
  • IMEI number of the device – You can get it by entering *#06# using the keypad.
  • The account holder’s phone number
  • The account holder’s Social Security number or password
  • A completed contract and/or device payment plan
  • Overseas deployment papers – This applies if the account holder is in the military and want to unlock his phone before his contract is up.


Unlocking a Verizon Phone

Verizon was not locking its devices before, but it’s doing it now. However, Verizon does it only for a short time. The newly purchased device will be locked to Verizon’s networks only for 60 days after the purchase. The lock will be automatically removed after 60 days. This applies both to prepaid and postpaid devices. Nevertheless, unlocking policies do not mention postpaid or prepaid 3G devices. However, under the previous procedure, there’s a need to enter a code, which is either “000000” or “123456” to enable third-party compatibility.


Unlocking an AT&T Phone

AT&T phone unlocking is a bit more complicated compared to Verizon. Here are some of the prerequisites for you to unlock your AT&T phone:

  1. The contract or installment plan must be already fully paid. If not, you need to pay your plan early. Also, you need to wait for 24 hours before making a request.
  2. The device must not have been reported lost, stolen, or involved in fraud.
  3. The account must have a good standing with AT&T.
  4. The device should not be registered with another AT&T user.
  5. The device in question should have been active for at least two months or 60 days. Moreover, if purchased on an installment plan, there should have “no past due or unpaid balance.”
  6. In case of early upgrading, there’s a need to wait for the 14-day “buyer’s remorse” period to pass before unlocking the old phone.
  7. For business devices, the company’s permission is needed.


In addition to this, AT&T offers an unlock request form that you can fill out online. You can either enter your AT&T mobile number or the IMEI number of your AT&T device. After you submit the form, you will be given 24 hours to click the link on the confirmation e-mail. AT&T will then give you a set of guidelines on how to unlock your phone. This will be done through e-mail, and you will receive it within two business days after the request was made. You can check on AT&T’s unlock status page to see if your request has been successful. For prepaid devices, they should be active for at least six months.


Unlocking a T-Mobile Phone

If you want to unlock your T-Mobile device, keep these in mind:

  1. The device must not have been reported lost, stolen, or blocked.
  2. Your account should be in good standing with T-Mobile.
  3. For postpaid accounts, the device must be already fully paid. Also, the device should have been active for 40 days.
  4. For prepaid accounts, the device must have refilled at least $100 since it was first used. Make sure your device has been active for over a year.
  5. Devices with service contracts should have at least 18 consecutive monthly payments made.
  6. If using T-Mobile’s Equipment Installment Plan, or if the phone is leased through JUMP! On-Demand, all payments must be made. Make sure that your device has been fully paid.
  7. The unlock request made in the last 12 months should be fewer than two per line.
  8. T-Mobile might ask for the proof of purchase.


To complete the unlocking process, some Android phones can use the T-Mobile Device Unlock app. However, for phones in which this app is not compatible, unlocking the phone can be done through a live chat with a T-Mobile customer service representative. Otherwise, the user can call 611 using a T-Mobile device. If they are using another phone, they can call 877-746-0909.


Unlocking a Sprint Device

If your Sprint device was launched after 2015, it will automatically unlock when they become eligible. However, if the device was launched earlier than that, there is still a process to unlock it. Nevertheless, the device and account should meet the following requirements to be unlocked.

  1. It must be domestic SIM Unlock capable.
  2. It must not have been reported lost, stolen or blocked, or involved in fraud.
  3. Of course, your account should have a good standing with Sprint.
  4. The device should have been active for at least 50 days on the requesting line.
  5. The owner must have no outstanding or pending payments or fees.


Some Sprint devices that come with a SIM slot can’t be unlocked. However, a user can request an unlock by chatting with Sprint. Another way is by calling 888-211-4727 (*2) using your Sprint device.


Differences Between Locked and Unlocked Phones

Differences Between Locked and Unlocked Phones
Photo by Liam Carrigan on GaijinPot Blog


Unlocked phones don’t have a software lock on it. Also, someone can get a code to unlock it. On the other hand, locked phones do have software code on it. This code hinders you from using it on another network.

Regarding the carrier, you can buy unlocked phones without a carrier. Usually, you can buy them without a SIM card. Furthermore, you don’t need to sign up for a service from a certain carrier. However, locked phones are tied with a particular carrier. These are usually sold through a wireless carrier. Also, you can buy them through a third-party of a particular carrier.

Locked phones are usable in only one network, while unlocked phones can be used in any network.


Advantages and Disadvantages of Unlocking Your Phone



  1. They give you the freedom to do what you want with your phone.
  2. You can have two SIM cards from different carriers.
  3. When you want to travel, using international SIM cards is easy.
  4. You can use your device to connect to Wi-Fi.
  5. There will be a lot of phone models to choose from.
  6. You have an option to buy used devices.
  7. You will receive frequent and faster software updates.
  8. They have higher resale value.
  9. You can find the best device that will suit your preferences at the best price possible.
  10. Unlocked phones don’t come with unwanted apps or bloatware.
  11. You will not have a penalty by switching carriers.
  12. You can easily replace your phone in case of theft. There’s no need to sign for a contract.



  1. You should have paid your device in full.
  2. They require you to be clever to easily use them.
  3. Some phones do not support particular network bands.
  4. It’s not easy to get help for the device.
  5. They do not come with different promotional discounts.
  6. Some unlocked phones are really expensive.
  7. They have no support from carriers.


Have Your Freedom With Unlocked Phones

People have different preferences when it comes to the phones that they are going to use. Some do prefer locked phones, while some prefer unlocked phones. If you don’t want to be tied to a specific carrier, an unlocked phone will be a better choice. You can have the freedom to choose your carrier. Also, you can have different SIM cards that you can use with your unlocked phone. Moreover, you can choose the best phone that will suit your preference while taking into account your budget. You can do whatever you want to do with your phone without minding the penalties. Furthermore, you are free to change your phone as you please.

If you want to read more guides for mobile phones, you can check out our articles about what are refurbished phones and the best gaming phones.