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expireddealsb posted Dec 13, 2021 1:28 AM

New Customers/Lines: 128GB Samsung Galaxy S21 5G Smartphone for T-Mobile

$400

$800

50% off
+ Free S/H (Activation Needed)at Best Buy
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Deal Details
Best Buy has for New Customers/New Lines: 128GB Samsung Galaxy S21 5G Smartphone for T-Mobile (Phantom Gray, SM-G991UZAATMB) on sale for $399.99 when you follow instructions below (purchase of this device will require activation due to being on T-Mobile network). Shipping is free, otherwise, select free curbside pickup as an alternative option.

Deal Instructions:
  1. Click here for 128GB Samsung Galaxy S21 5G Smartphone for T-Mobile (Phantom Gray)
  2. Select Activate Today then add to cart
  3. Select T-Mobile then click continue
  4. Select Add a New Line or Create a New Account
  5. Continue to follow on-screen instructions
  6. Your total will be $399.99 + free shipping
Thanks to Community member dealsb for finding this deal.

Specs (source):
  • 6.2" 2400 x 1080 120Hz Dynamic AMOLED 2X Gorilla Glass Victus
  • Qualcomm Snapdragon 888 1.8 GHz Kryo 680 Quad-Core Processor
  • 8GB RAM
  • 128GB Storage
  • Wi-Fi 6E (802.11ax) + Bluetooth 5.0 + LE
  • Fingerprint Sensor (Under-Screen)
  • Android 11
  • Rear Camera:
    • Telephoto: 64 MP 1/1.76" Sensor (0.8 µm Pixels) with a 28mm f/2.0 Lens
    • Wide: 12 MP 1/1.76" Sensor (1.8 µm Pixels) with a 26mm f/1.8 Lens
    • Ultra Wide: 12 MP 1/2.6" Sensor (1.4 µm Pixels) with a 13mm f/2.2 Lens (120° FoV)
  • Front Camera:
    • Standard: 10 MP 1/3.2" Sensor (1.22 µm Pixels) with a 26mm f/2.2 Lens
  • Ports
    • 1x USB Type-C (USB 3.1 / USB 3.2 Gen 1)
    • 1x Nano SIM

Editor's Notes

Written by slickdewmaster | Staff
  • About this deal:
    • This price is $400 lower (50% savings) than the list price of $799.99
  • About this Product:
    • Limited 1-year manufacturer's warranty.
  • About this store::

Original Post

Written by dealsb
Community Notes
About the Poster
Deal Details
Community Notes
About the Poster
Best Buy has for New Customers/New Lines: 128GB Samsung Galaxy S21 5G Smartphone for T-Mobile (Phantom Gray, SM-G991UZAATMB) on sale for $399.99 when you follow instructions below (purchase of this device will require activation due to being on T-Mobile network). Shipping is free, otherwise, select free curbside pickup as an alternative option.

Deal Instructions:
  1. Click here for 128GB Samsung Galaxy S21 5G Smartphone for T-Mobile (Phantom Gray)
  2. Select Activate Today then add to cart
  3. Select T-Mobile then click continue
  4. Select Add a New Line or Create a New Account
  5. Continue to follow on-screen instructions
  6. Your total will be $399.99 + free shipping
Thanks to Community member dealsb for finding this deal.

Specs (source):
  • 6.2" 2400 x 1080 120Hz Dynamic AMOLED 2X Gorilla Glass Victus
  • Qualcomm Snapdragon 888 1.8 GHz Kryo 680 Quad-Core Processor
  • 8GB RAM
  • 128GB Storage
  • Wi-Fi 6E (802.11ax) + Bluetooth 5.0 + LE
  • Fingerprint Sensor (Under-Screen)
  • Android 11
  • Rear Camera:
    • Telephoto: 64 MP 1/1.76" Sensor (0.8 µm Pixels) with a 28mm f/2.0 Lens
    • Wide: 12 MP 1/1.76" Sensor (1.8 µm Pixels) with a 26mm f/1.8 Lens
    • Ultra Wide: 12 MP 1/2.6" Sensor (1.4 µm Pixels) with a 13mm f/2.2 Lens (120° FoV)
  • Front Camera:
    • Standard: 10 MP 1/3.2" Sensor (1.22 µm Pixels) with a 26mm f/2.2 Lens
  • Ports
    • 1x USB Type-C (USB 3.1 / USB 3.2 Gen 1)
    • 1x Nano SIM

Editor's Notes

Written by slickdewmaster | Staff
  • About this deal:
    • This price is $400 lower (50% savings) than the list price of $799.99
  • About this Product:
    • Limited 1-year manufacturer's warranty.
  • About this store::

Original Post

Written by dealsb

Community Voting

Deal Score
+110
Good Deal
Visit Best Buy

Price Intelligence

Model: Samsung - Galaxy S21 5G 128GB (Unlocked) - Phantom Gray

Deal History 

Sale Price
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Current Prices

Sort: Lowest to Highest | Last Updated 7/26/2026, 10:43 PM
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700 Comments

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Dec 14, 2021 3:17 PM
66 Comments
Joined May 2010
fsiddiqueDec 14, 2021 3:17 PM
66 Comments
Just bought selecting Magenta Max and created a new account. Will try to call and cancel the new account prior to activation after device gets delivered.
Dec 14, 2021 3:21 PM
17 Comments
Joined Feb 2021
GreenDolphin686Dec 14, 2021 3:21 PM
17 Comments
Quote from fsiddique :
Just bought selecting Magenta Max and created a new account. Will try to call and cancel the new account prior to activation after device gets delivered.
confirm if you did not have a problem for canceling
Dec 14, 2021 3:42 PM
118 Comments
Joined Jul 2018
ImBrokeSoWhatDec 14, 2021 3:42 PM
118 Comments
Quote from resseeker :
Interested to hear someone's actual experience.. when you go to add to cart it asks which carrier you want to activate on. Cheapest being TMO, but it has to be a new line/account. Wondering how this works out if you create a new account and purchase/terminate.
Same here. I almost pulled the trigger when I finished filling out the TMO account information part. Backed out because I was afraid that maybe they will do a early cancellation service fee and still charge you for the 1 month of service. Even though it said $435 for the phone, my fear is that in the end it could come out higher. What a headache.
3
Dec 14, 2021 3:53 PM
165 Comments
Joined Apr 2016
nimpraviDec 14, 2021 3:53 PM
165 Comments
Quote from fsiddique :
Just bought selecting Magenta Max and created a new account. Will try to call and cancel the new account prior to activation after device gets delivered.
How did you order? Did you order through their website or app? I am consistently getting the error no matter what plan I select.
Dec 14, 2021 5:13 PM
64 Comments
Joined May 2018
Slickdealer5554Dec 14, 2021 5:13 PM
64 Comments
This seems like a great deal, just add a line or make a new account , pay best buy for the phone, then just immediately cancel the line or account.
Dec 14, 2021 6:20 PM
66 Comments
Joined May 2010
fsiddiqueDec 14, 2021 6:20 PM
66 Comments
Quote from nimpravi :
How did you order? Did you order through their website or app? I am consistently getting the error no matter what plan I select.
Ordered thru the browser on mobile. I recall reading in the other thread (Galaxy Z) that error is indicative of the automated system unable to authenticate a credit check matching SSN with DL info, but not sure if that is correct...
Dec 14, 2021 7:14 PM
165 Comments
Joined Apr 2016
nimpraviDec 14, 2021 7:14 PM
165 Comments
Quote from fsiddique :
Just bought selecting Magenta Max and created a new account. Will try to call and cancel the new account prior to activation after device gets delivered.
As online purchase errored out, I purchased in store. Convinced store associate not to open the box. So, I came out with unopened s21 and a Tmo SIM card. I remember store associate mentioning that number will not be activated till I insert SIM into the phone.

Now I am curious on what happens if I never insert SIM into the phone and use the phone with other carrier? Do I still need to call Tmo to cancel the line (line is technically not yet active, I suppose)? If I call them, what should I tell them as I don't even have Tmo phone number and I won't get that till I insert SIM into the phone.

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Dec 14, 2021 7:16 PM
12.5K Comments
Joined Mar 2008
pokymonDec 14, 2021 7:16 PM
12.5K Comments
Is this better than OnePlus 8 for $249?
1
Dec 14, 2021 8:08 PM
1K Comments
Joined Nov 2010
hellwithuDec 14, 2021 8:08 PM
1K Comments
I am an existing T-mobile user. I dont want to add any new line.

Can anyone please explain me what is "upgrade" mean in T-mobile?
Dec 14, 2021 8:42 PM
1.3K Comments
Joined Nov 2011
resseekerDec 14, 2021 8:42 PM
1.3K Comments
Quote from nimpravi :
As online purchase errored out, I purchased in store. Convinced store associate not to open the box. So, I came out with unopened s21 and a Tmo SIM card. I remember store associate mentioning that number will not be activated till I insert SIM into the phone.

Now I am curious on what happens if I never insert SIM into the phone and use the phone with other carrier? Do I still need to call Tmo to cancel the line (line is technically not yet active, I suppose)? If I call them, what should I tell them as I don't even have Tmo phone number and I won't get that till I insert SIM into the phone.
They should not be doing this anyways.

Quote from nimpravi :
Now I am curious on what happens if I never insert SIM into the phone and use the phone with other carrier? Do I still need to call Tmo to cancel the line (line is technically not yet active, I suppose)? If I call them, what should I tell them as I don't even have Tmo phone number and I won't get that till I insert SIM into the phone.
Per the post above and from the other thread, you'll get billed.. however you need to call TMO provide them with the phone numbers OR SIM Card info of the new account/line and tell them to cancel it. Otherwise you'll get billed. Once the line is cancelled (you shouldn't have an issue with this since you never actually popped the sim in/activated). You'll cancel your TMO service and have the phone for $400 + Tax.
Dec 14, 2021 8:42 PM
1.3K Comments
Joined Nov 2011
resseekerDec 14, 2021 8:42 PM
1.3K Comments
Just to update, I needed to replace a few phones in the household and was able to do this on the mobile website (vs. laptop) without encountering that error. Weird.. but hey it worked. Now I'm going to pick up and terminate the lines.
Dec 14, 2021 8:45 PM
165 Comments
Joined Apr 2016
nimpraviDec 14, 2021 8:45 PM
165 Comments
Quote from resseeker :
They should not be doing this anyways.



Per the post above and from the other thread, you'll get billed.. however you need to call TMO provide them with the phone numbers OR SIM Card info of the new account/line and tell them to cancel it. Otherwise you'll get billed. Once the line is cancelled (you shouldn't have an issue with this since you never actually popped the sim in/activated). You'll cancel your TMO service and have the phone for $400 + Tax.
Thanks for the response. Is there a way to know the phone number without inserting the SIM into the device? I didn't get the phone number from best buy store associate.
Dec 14, 2021 8:52 PM
1.8K Comments
Joined Mar 2007
kevin347Dec 14, 2021 8:52 PM
1.8K Comments
Quote from resseeker :
Just to update, I needed to replace a few phones in the household and was able to do this on the mobile website (vs. laptop) without encountering that error. Weird.. but hey it worked. Now I'm going to pick up and terminate the lines.
Was your total just 399 plus tax when you placed order?Can you confirm how the cancellation with tmobil worked for you and can you ask them if they are going to send any other bill with activation fees etc? And how long if there will be a bill generated.
Dec 14, 2021 8:56 PM
2.1K Comments
Joined Feb 2007
techie333Dec 14, 2021 8:56 PM
2.1K Comments
I get this, I'm on an old simple choice plan through t-mobile and tried to add a line. Any way around this?
Quote :
Carrier has restrictions
T-Mobile is telling us that Best Buy is not currently able to complete adding a line on this account.
Please contact T-Mobile for additional details.

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Dec 14, 2021 8:57 PM
158 Comments
Joined Jan 2013
rja142Dec 14, 2021 8:57 PM
158 Comments
Am I correct that phones nowadays can be easily moved among networks? Could I do this deal and then use it on Verizon?

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