Galaxy S21 Ultra 5G • UnlockedBlack • 128 GB • Physical SIM + eSIM

(1,429 reviews)

$243.79

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Free delivery by Sep 16 - 17

Express delivery by Sep 15 - 16 from $15.00

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Customer reviews for Galaxy S21 Ultra 5G • Unlocked

Overall rating

1,429 verified reviews

Rating details

Accessories
4.1/5
Appearance
4.2/5
Battery
4.2/5
Lens & Camera
4.4/5
Overall performance
4.2/5
Packaging
4.4/5
Shipping
4.5/5

Reviews

Billy H.
Verified purchase
Reviewed 11/27/25, United States.
Wow, kudos to Black Market for their novel approach to sales: selling brand new, flawless phones as 'refurbished'. I mean, who needs transparency, right? It's not like customers might feel misled when they get a phone that's literally perfect. But seriously... But let's talk about my recently purchased Samsung Galaxy S21 Ultra - it's a stunning device. The display is vibrant, the camera is incredible, and performance is top-notch. I mean, you'd never guess it's refurbished; it looks and performs like brand new! If you're in the market for a high-end device and want a brand new phone at a refurbished price (wink), I'd say go for it. Just don't try to tell anyone it's 'refurbished'. HA! Product: Samsung Galaxy S21 Ultra Rating: 5/5 stars (for the product, and the sales pitch)
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Condition
Excellent
Almost no signs of wear. The body may have very light micro-scratches. For items with screens, the screen will have no scratches.
Purchased
11/12/25
Christine P.
Verified purchase
Reviewed 2/15/26, United States.
I love my Galaxy S21, it is quite a bit larger than my last phone. I don't know why it took me so long to upgrade. Never disappointed with buying from Back Market.
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Condition
Excellent
Almost no signs of wear. The body may have very light micro-scratches. For items with screens, the screen will have no scratches.
Purchased
2/7/26
Christopher T.
Verified purchase
Reviewed 9/7/26, United States.
I love this device. Do your research like I did. Even for a 5 year old device, It still out preforms every new budget device for less money. Great for someone who cant afford a $1200 dollar, but still values performance in their device. I spent $300 for phone, phone case and screen protector. Will buy my next phone here
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Condition
Fair
Signs of wear. The body may have a few visible scratches and dents. Items with screens may have light scratches.
Purchased
8/27/26
Wynsergs rave M.
Verified purchase
Reviewed 1/2/26, United States.
This is so super great, when i had it this phone it makes me happy that i bought my dream phone that i earned. I don't have to waste a thousand dollar for this phone. The performance was so great you won't realize that is a refurbished after all, from the good pictures of taking photos on camera to the perfomance when you take so much apps. For the great price of 200 dollars you can have a great phone for taking pictures and high graphics on playing online games.
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Condition
Fair
Signs of wear. The body may have a few visible scratches and dents. Items with screens may have light scratches.
Purchased
12/25/25
Philip H.
Verified purchase
Reviewed 10/13/25, United States.
I was very sceptical about buying a refurbished phone, but after reading other reviews I took the chance and I'm glad I did. I purchased for my wife so that we can have the same phones. The only issue, may not be an issue, is there is three permanent light hard to see rings, about the size of a small button on the screen, it's only visible in photos when looking at pictures, other than that, the phone is perfect. I highly recommend others to purchase their phones through back market.
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Condition
Fair
Signs of wear. The body may have a few visible scratches and dents. Items with screens may have light scratches.
Purchased
9/24/25
Arthur D.
Verified purchase
Reviewed 8/20/26, United States.
This is the second used ultra I've gotten from back market and they are just excellent they refurbished refinish and great pricing I will always buy my phone from them
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Condition
Fair
Signs of wear. The body may have a few visible scratches and dents. Items with screens may have light scratches.
Purchased
8/11/26
Heath W.
Verified purchase
Reviewed 7/10/26, United States.
It's in perfect condition! I've always owned cheaper smart phones that you get through Boost most were OK but I got so used to their operating system that it has been tough for me to figure out the galaxy! So different but I like it and Back Market you sent me exactly what you said I would get! Thank you! Honesty is hard to come by these days!
Galaxy S21 Ultra 5G 128GB - Silver - Unlocked
Galaxy S21 Ultra 5G 128GB - Silver - Unlocked
Condition
Excellent
Almost no signs of wear. The body may have very light micro-scratches. For items with screens, the screen will have no scratches.
Purchased
7/2/26

Everything you ever wanted to know about the Galaxy S21 Ultra 5G • Unlocked

Durability
Overall performance
Camera
Screen quality

SM-G998UZKAXAAMPN
Dynamic AMOLED 2XScreen type
2021Release Year
6.8Screen size (inches)
YesLast OS Compatibility
USB-CConnector
NoFoldable
NoMemory Card Slot
SM-G998U1Manufacturer Ref.

The Galaxy S21 Ultra 5G is a high-end flagship smartphone that was released in early 2021. It is known for its powerful performance, versatile camera system, and 5G connectivity. This model is the 128GB variant, offering ample storage for everyday use. As a refurbished device, it provides a cost-effective option for those seeking premium features at a lower price point.

Key features:

Model: Galaxy S21 Ultra 5G
Display: 6.8-inch Dynamic AMOLED 2X, 120Hz refresh rate
Processor: Exynos 2100 (Global) or Snapdragon 888 (USA)
Camera: Quad-camera system with 108MP main sensor, 12MP periscope telephoto, 10MP telephoto, and 12MP ultra-wide
Connectivity: 5G capable for fast data speeds

Who is this for?

The Galaxy S21 Ultra 5G is suitable for users who want a premium Android device with a large, vibrant display, advanced photography capabilities, and 5G support. It’s ideal for tech enthusiasts, content creators, or anyone needing a powerful, versatile smartphone.

Pros & Cons: Pros Cons Large, high-resolution display with 120Hz refresh rate. Bulkier size may be less comfortable for one-handed use. Advanced quad-camera system for versatile photography. Battery life varies depending on usage, but some users may find it less enduring under heavy load.
Why refurbished?

Choosing a refurbished Galaxy S21 Ultra 5G allows you to access a premium device at a more accessible price. Each device is tested and certified to meet quality standards, ensuring reliable performance. Refurbished devices from Back Market undergo rigorous quality checks to guarantee top condition. Learn more about our quality standards.

MPN: SM-G998UZKAXAA
Screen type: Dynamic AMOLED 2X
Release Year: 2021
Screen size (inches): 6.8
Last OS Compatibility: Yes
Connector: USB-C
Foldable: No
Memory Card Slot: No
Manufacturer Ref.: SM-G998U1
Brand: Samsung
Color: Black
Storage: 128 GB
Carrier compatibility: Unlocked
Resolution: 1440 x 3200
Serie: Samsung Galaxy S
OS: Android
SAR body: 1.02
Weight: 8 oz
Main camera: 108 megapixels
SAR head: 0.77
Network: 5G
Front camera: 40 megapixels
Model: Galaxy S21 Ultra 5G
Color (official name): Phantom Black
SIM card: Physical SIM + eSIM
Memory (GB): 12 GB

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Galaxy S21 Ultra 5G • UnlockedBlack • 128 GB • Physical SIM + eSIM

Galaxy S21 Ultra 5G • UnlockedBlack • 128 GB • Physical SIM + eSIM

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Customer reviews for Galaxy S21 Ultra 5G • Unlocked

Overall rating

Rating details

Reviews

Reviews

Billy H.

Christine P.

Christopher T.

Wynsergs rave M.

Philip H.

Arthur D.

Heath W.

Popular searches

Everything you ever wanted to know about the Galaxy S21 Ultra 5G • Unlocked

Durability

Overall performance

Camera

Screen quality

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