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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
245K Views
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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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  • Today

Current Prices

Sort: Lowest to Highest | Last Updated 7/26/2026, 10:43 PM
Sold By Sale Price
NewEgg$649.99

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700 Comments

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Dec 15, 2021 1:34 PM
2.5K Comments
Joined Oct 2013
Requiem2242Dec 15, 2021 1:34 PM
2.5K Comments
Quote from Ride_The_Sky :
Could someone comment on upgrades?
Yes. Just pay Best Buy the 499 and your done. No extra charges
Dec 15, 2021 4:22 PM
354 Comments
Joined Jul 2019
WickaFlickaDec 15, 2021 4:22 PM
354 Comments
Quote from SlikRick :
but they'll charge for the first month won't they?
They generate a bill after 15 days of account opening. You can get any charges waved/refunded within the first 30 days of service under their buyers remorse policy.
Dec 15, 2021 4:49 PM
320 Comments
Joined Nov 2009
tefunkDec 15, 2021 4:49 PM
320 Comments
Quote from maxblockm :
Maybe this?

Cancellation Policy. You may cancel your Rate Plan by going back to the original point of purchase and returning all devices you acquired with your activation within 30 days from your activation date (Cancellation Period). You may have to pay a restocking fee for any Device you return.


and on the checkout page

A restocking fee applies to one or more items in your order, if they are opened and returned. Restocking Fee: $45



I was getting that with my wife's info, even in incognito. Used my info on the same window and it worked.
One earlier post said to first put in a different sim in the phone and then call T-Mobile to cancel. I wonder if I should cancel first so I don't open the box in case I need to return it.
Dec 15, 2021 4:51 PM
7.4K Comments
Joined Jul 2004
BrooklyniteDec 15, 2021 4:51 PM
7.4K Comments
Quote from dealsb :
No clue why no one found it exciting. I did it earlier today and felt it to be a great price for an unlocked current flagship phone.
Are you sure there is zero committment? TMobile could black list the phone is not fully paid, no?
4
Dec 15, 2021 5:11 PM
795 Comments
Joined Oct 2015
theothercrazybrianDec 15, 2021 5:11 PM
795 Comments
Quote from garyham100 :
Why do people post with opinions...not fact. On the One Plus 8 and up models, One Plus has committed to three major system updates....Since Android 11 is an update, Android 12 and 13 should be supported. Also One Plus has committed to four years of security updates.
My OnePlus 8T 5G has worked flawless... I've been very impressed. I got a great deal on it, so that might make a difference.
But man- I could not live without warp charging now. Phone low? Oh yeah plug it in for 30 mins and youre good to go for the rest of the entire day.
It'll hurt if my next phone doesn't have it, but alas, who knows.
1
Dec 15, 2021 8:15 PM
165 Comments
Joined Apr 2016
nimpraviDec 15, 2021 8:15 PM
165 Comments
Quote from dealsb :
You should be able to cancel with the sim number which will be on the Sim card.
I called Tmo customer service and tried cancelling the account. But, they told that they can't pull my details unless I provide either account number or phone number or order number. Since I don't have any of these, they asked me to check with Best Buy. Is there a specific number do I need to call where they can cancel with just SIM number?
Dec 15, 2021 9:28 PM
1.3K Comments
Joined Nov 2011
resseekerDec 15, 2021 9:28 PM
1.3K Comments

Our community has rated this post as helpful. If you agree, why not thank resseeker

For everyone looking for how to finesess this deal:

1. Follow steps as mentioned in Wiki (if you get that error, its most likely a authentication error where TMO can't verify your credentials i.e. social w/ ID) you can try doing this in person at a BB store. I was getting this error despite checking everything 15x, finally tried doing it on the mobile BB site and it worked.
2. Do not insert your SIM into the phone. When you sign up online, as you are about to check out, you'll have to agree with the tmobile terms and conditions.. THIS IS WHERE YOUR PHONE NUMBER IS LISTED. WRITE IT DOWN OR SCREENSHOT.
3. Call 1 800 T MOBILE, tell CS agent that you wish to cancel the line (you can make up whatever excuse you want)
4. If they mention "are you returning a device to the store?" say NO. There is no device associated with your new line/account.
5. They'll cancel your account effective immediately.
6. The phone is FACTORY UNLOCKED, can be used with any compatible provider.

I was able to do this process for 2 phones. $400+tax for a FACTORY UNLOCKED S21 5G is a great deal imo.
Last edited by resseeker December 15, 2021 at 01:30 PM.
3
3

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Dec 15, 2021 9:47 PM
23 Comments
Joined Sep 2009
airmarcusDec 15, 2021 9:47 PM
23 Comments
Quote from resseeker :
For everyone looking for how to finesess this deal:

1. Follow steps as mentioned in Wiki (if you get that error, its most likely a authentication error where TMO can't verify your credentials i.e. social w/ ID) you can try doing this in person at a BB store. I was getting this error despite checking everything 15x, finally tried doing it on the mobile BB site and it worked.
2. Do not insert your SIM into the phone. When you sign up online, as you are about to check out, you'll have to agree with the tmobile terms and conditions.. THIS IS WHERE YOUR PHONE NUMBER IS LISTED. WRITE IT DOWN OR SCREENSHOT.
3. Call 1 800 T MOBILE, tell CS agent that you wish to cancel the line (you can make up whatever excuse you want)
4. If they mention "are you returning a device to the store?" say NO. There is no device associated with your new line/account.
5. They'll cancel your account effective immediately.
6. The phone is FACTORY UNLOCKED, can be used with any compatible provider.

I was able to do this process for 2 phones. $400+tax for a FACTORY UNLOCKED S21 5G is a great deal imo.
Stuck on the error. Tried every browser I could think of...
1
Dec 15, 2021 10:25 PM
75 Comments
Joined Aug 2007
dihorulDec 15, 2021 10:25 PM
75 Comments
Quote :
Quote from resseeker :
For everyone looking for how to finesess this deal:

1. Follow steps as mentioned in Wiki (if you get that error, its most likely a authentication error where TMO can't verify your credentials i.e. social w/ ID) you can try doing this in person at a BB store. I was getting this error despite checking everything 15x, finally tried doing it on the mobile BB site and it worked.
2. Do not insert your SIM into the phone. When you sign up online, as you are about to check out, you'll have to agree with the tmobile terms and conditions.. THIS IS WHERE YOUR PHONE NUMBER IS LISTED. WRITE IT DOWN OR SCREENSHOT.
3. Call 1 800 T MOBILE, tell CS agent that you wish to cancel the line (you can make up whatever excuse you want)
4. If they mention "are you returning a device to the store?" say NO. There is no device associated with your new line/account.
5. They'll cancel your account effective immediately.
6. The phone is FACTORY UNLOCKED, can be used with any compatible provider.

I was able to do this process for 2 phones. $400+tax for a FACTORY UNLOCKED S21 5G is a great deal imo.
resseekerFor everyone looking for how to finesess this deal:

1. Follow steps as mentioned in Wiki (if you get that error, its most likely a authentication error where TMO can't verify your credentials i.e. social w/ ID) you can try doing this in person at a BB store. I was getting this error despite checking everything 15x, finally tried doing it on the mobile BB site and it worked.
2. Do not insert your SIM into the phone. When you sign up online, as you are about to check out, you'll have to agree with the tmobile terms and conditions.. THIS IS WHERE YOUR PHONE NUMBER IS LISTED. WRITE IT DOWN OR SCREENSHOT.
3. Call 1 800 T MOBILE, tell CS agent that you wish to cancel the line (you can make up whatever excuse you want)
4. If they mention "are you returning a device to the store?" say NO. There is no device associated with your new line/account.
5. They'll cancel your account effective immediately.
6. The phone is FACTORY UNLOCKED, can be used with any compatible provider.
I didn't get the number or screenshot it yesterday, how should I find the number now?
Dec 15, 2021 11:00 PM
15.9K Comments
Joined Jan 2010
Ride_The_SkyDec 15, 2021 11:00 PM
15.9K Comments
Is S21 Ultra $800 a bad deal? I mean it hasn't been any better than $1000 until recently, so I am wondering..
Dec 15, 2021 11:45 PM
1.3K Comments
Joined Nov 2011
resseekerDec 15, 2021 11:45 PM
1.3K Comments
Quote from dihorul :
I didn't get the number or screenshot it yesterday, how should I find the number now?
They can probably pull it off your SIM Card #.
Dec 15, 2021 11:54 PM
323 Comments
Joined Nov 2006
sduser1Dec 15, 2021 11:54 PM
323 Comments
Quote from resseeker :
For everyone looking for how to finesess this deal:

1. Follow steps as mentioned in Wiki (if you get that error, its most likely a authentication error where TMO can't verify your credentials i.e. social w/ ID) you can try doing this in person at a BB store. I was getting this error despite checking everything 15x, finally tried doing it on the mobile BB site and it worked.
2. Do not insert your SIM into the phone. When you sign up online, as you are about to check out, you'll have to agree with the tmobile terms and conditions.. THIS IS WHERE YOUR PHONE NUMBER IS LISTED. WRITE IT DOWN OR SCREENSHOT.
3. Call 1 800 T MOBILE, tell CS agent that you wish to cancel the line (you can make up whatever excuse you want)
4. If they mention "are you returning a device to the store?" say NO. There is no device associated with your new line/account.
5. They'll cancel your account effective immediately.
6. The phone is FACTORY UNLOCKED, can be used with any compatible provider.

I was able to do this process for 2 phones. $400+tax for a FACTORY UNLOCKED S21 5G is a great deal imo.
When you did this for 2 phones - was it two times from start to cancel or did you somehow open one account with 2 lines and then closed it?
Dec 16, 2021 12:09 AM
159 Comments
Joined Feb 2019
BoyinthecloudDec 16, 2021 12:09 AM
159 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.
What's the other thread?
Dec 16, 2021 12:22 AM
31 Comments
Joined Jul 2009
hockeymachine86Dec 16, 2021 12:22 AM
31 Comments
Anyone know if this would work to port a current sprint number in?

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Dec 16, 2021 12:54 AM
1.4K Comments
Joined Jun 2007
fyugiohDec 16, 2021 12:54 AM
1.4K Comments
Quote from airmarcus :
Stuck on the error. Tried every browser I could think of...
After getting the error for the basic plan, I switch to Magenta Max plan and it worked.

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