Galaxy S21 Ultra 5G 128GB - Dark Blue - Unlocked

All devices are restored professionally based on a 25-point inspection

Buttons
SIM/memory card reader
Data deletion
Chargers/cables
Unlocked by previous owner
GPS/positioning system
Cameras
External sensors
Biometric sensors
Wi-Fi and Bluetooth
IMEI serial number
Water damage
Flash and indicator lights
Mics and speakers
Input and output ports
Phone carrier
Battery health
Mechanical parts
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Galaxy S21 Ultra 5G 128GB - Dark Blue - Unlocked's customer reviews

979 verified reviews in the last 24 months.

O
Olivia L.
Purchased on March 23, 2025
Verified purchase
I was a bit hesitant to order my phone at first since I’d never bought a refurbished device before, and I had seen a few negative reviews on social media. But I decided to give it a try, and I’m so glad I did! The shipping was quick, the phone looks brand new, and it runs perfectly — you’d never guess it’s refurbished. I’ll definitely be ordering again!
Condition
Almost no signs of wear. The body may have very light micro-scratches. For items with screens, the screen will have no scratches.
Excellent
Item
Galaxy S21 Ultra 5G 128GB - Silver - Unlocked
Reviewed in the United States on April 7, 2025
M
Michael t W.
Purchased on September 11, 2024
Verified purchase
This is my fourth phone Ive gotten from backmarket!! WHY? Because searching the net up and down ..Backmarket alwasy seemed tpo have the best deal.One big reason is the first two had clear new screens and the phone was refurbished.This time i got a galaxy s21..It is brand new looking..Super good phone.Super happy-PEACE
Condition
Light signs of wear. The body may have light micro-scratches. For items with screens, the screen will have no scratches.
Good
Item
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Reviewed in the United States on November 11, 2024
M
Michael E.
Purchased on February 2, 2024
Verified purchase
The Samsung S21 Ultra appears to be fine in the two weeks since we received it and was as promised. Ordering was easy and delivery was as expected. Our trade-in offer was much lower than we had anticipated ($25.00) for a phone in complete working order without problems. I have previously purchased certified, refurbished smartphones directly from Samsung and felt we received a much better & fairer trade-in offer. While the price of the S21 Ultra was cheaper from Back Market, I believe that I might have fared better buying from Samsung in terms of overall cost. I will research more closely when it's time for our next purchase.
Condition
Almost no signs of wear. The body may have very light micro-scratches. For items with screens, the screen will have no scratches.
Excellent
Item
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Reviewed in the United States on February 18, 2024
J
Jennifer U.
Purchased on October 29, 2023
Verified purchase
I was very very skeptical about buying a refurbished phone. I debated about it for months. When my son bought a refurbished iPhone that looked brand new, and worked perfectly I decided to go for it! I was not disappointed! I got the Samsung galaxy S21 Ultra in excellent condition. It came quicker than expected and there were no noticeable scratches or dings on the back, there was a tiny scratch on the screen which you cannot even see with the screen on. Overall I am super satisfied with the phone, I got a great deal on an awesome phone! I will definitely buy from Backmarket again!
Condition
Signs of wear. The body may have a few visible scratches and dents. Items with screens may have light scratches.
Fair
Item
Galaxy S21 Ultra 5G 128GB - Silver - Unlocked
Reviewed in the United States on November 12, 2023
G
Gerald P.
Purchased on March 10, 2024
Verified purchase
Trading in my beat-up S21Ultra with damaged screen for this excellent condition replacement enabled me to, in turn, take advantage of trade-in promotion at Samsung Store. My old phone was worthless for trade-in otherwise. The refurbisher who purchased my trade-in tried to claim that it didn't take a charge... but with my photos in hand, the Backmarket staff swiftly dealt with that. Be sure to take photos of live phone, and of each stage of packaging, so that Backmarket is able to support you in case of dispute. Great customer service!
Condition
Almost no signs of wear. The body may have very light micro-scratches. For items with screens, the screen will have no scratches.
Excellent
Item
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Reviewed in the United States on March 24, 2024
G
Geraldine M.
Purchased on January 23, 2025
Verified purchase
The Galaxy S21 Ultra 5G 128G Black is a nice phone. It had one slight scratch although the description said Excellent Condition with no visible marks. Both phones had visible marks. We liked the phone in spite of this.
Condition
Close to perfection. The body may have tiny micro-scratches. For items with screens, the screen will be flawless.
Premium
Item
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Reviewed in the United States on February 10, 2025
S
Sheddrick S.
Purchased on December 20, 2024
Verified purchase
No complaints here. Came as described, quality holds up extremely well compared to newer gens, definitely worth the price
Condition
Almost no signs of wear. The body may have very light micro-scratches. For items with screens, the screen will have no scratches.
Excellent
Item
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Reviewed in the United States on January 7, 2025

Everything you ever wanted to know about the Galaxy S21 Ultra 5G 128GB - Dark Blue - Unlocked

SM-G998UZKAXAAManufacturing part numbers (MPN)
Dark BlueColor
6.8Screen size (inches)
Galaxy S21 Ultra 5GModel
AndroidOS
1440 x 3200Resolution
USB-CConnector
UnlockedCarrier compatibility
128 GBStorage

The Galaxy S21 Ultra 5G is a flagship smartphone from Samsung that offers high-end features and performance. This model is part of the S21 series, launched in early 2021, and provides a premium experience with a focus on photography, display quality, and connectivity. It is sold unlocked, making it compatible with various carriers worldwide.

Key features:

Display: 6.8-inch Dynamic AMOLED 2X, 1440 x 3200 pixels, with 120Hz refresh rate
Processor: Exynos 2100 (Global) or Snapdragon 888 (USA)
Camera: Quad-camera system with a 108MP main sensor, 12MP periscope telephoto, 10MP telephoto, and 12MP ultra-wide
Connectivity: 5G capable for fast data transfer and low latency
Storage: 128GB internal storage (not expandable)

Who is this for?

The Galaxy S21 Ultra 5G 128GB is suitable for users seeking a powerful device for photography, multimedia consumption, and multitasking. It’s ideal for tech enthusiasts, professionals, or anyone wanting a premium Android experience with 5G connectivity.

Pros & Cons:

Pros	Cons
Large, vibrant display with high refresh rate	No microSD card slot for expandable storage
Exceptional camera system with high-resolution sensors	Battery life may vary depending on usage

Why refurbished?

Choosing a refurbished Galaxy S21 Ultra 5G allows you to access a premium device at a more accessible price point. Each device undergoes rigorous testing to meet Back Market’s quality standards, ensuring reliability and good condition. Learn more about our quality standards.

Galaxy S21 Ultra 5G 128GB - Dark Blue - Unlocked
Manufacturing part numbers (MPN)	SM-G998UZKAXAA
Color	Dark Blue
Screen size (inches)	6.8
Model	Galaxy S21 Ultra 5G
OS	Android
Resolution	1440 x 3200
Connector	USB-C
Carrier compatibility	Unlocked
Storage	128 GB
Memory	12 GB
Screen type	Dynamic AMOLED 2X
Network	5G
Manufacturer Ref.	SM-G998U1
Memory Card Slot	No
Verizon compatible	Yes
AT&T compatible	Yes
T-Mobile compatible	Yes
Last OS Compatibility	Yes
Foldable	No
Front camera	40 megapixels
SAR head	0.77
SAR body	1.02
Series	Samsung Galaxy S
SIM card	Physical SIM + eSIM
Retro tech	No
Main camera	108 megapixels
Color (official name)	Phantom Navy
Release Year	2021
Company name	Samsung Electronics
Company email address	support@samsung.com
Company postal address	Samsung House, 1000 Hillswood Drive, Chertsey, Surrey, KT16 0PS, UK
Brand	Samsung
Weight	8 oz