Galaxy S21 Ultra 5G • UnlockedBlack • 256 GB • Physical SIM + eSIM

(1,398 reviews)

$617.92

Save $408.28

Free delivery by Jun 10 - 11

Express delivery by Jun 9 - 10 from $9.99

Restored professionally

Based on up to 100 points of inspection

Customer reviews for Galaxy S21 Ultra 5G • Unlocked

Overall rating

1,398 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

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
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
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
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
Nikki H.
Verified purchase
Reviewed 2/25/26, United States.
This is a great backup phone. Despite the "fair" condition it only has a scratch on the screen which isn't noticeable while using it. The functionality it's perfect and what I expect from a Samsung S series.
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
2/11/26
Joe M.
Verified purchase
Reviewed 3/19/26, United States.
It's Great 👍 Really User friendly. lots memory for pictures and for different apps . She really like the Big Screen and the camera Takes Awesome Pictures and videos . Would recommend it Anyone looking for a Great Phone 📱
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
3/8/26
Olivia L.
Verified purchase
Reviewed 4/7/25, United States.
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!
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
3/23/25

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

Durability
Overall performance
Camera
Screen quality

SM-G998UZKEXAAMPN
NoFoldable
Samsung Galaxy SSerie
40 megapixelsFront camera
0.77SAR head
Physical SIM + eSIMSIM card
Phantom BlackColor (official name)
SM-G998UManufacturer Ref.
1.02SAR body

The Galaxy S21 Ultra 5G is a flagship-level smartphone from Samsung, introduced in early 2021. It offers a blend of high-end features suitable for users who need a powerful device for multimedia, photography, and multitasking. As a pre-owned device, it provides a cost-effective option for those seeking premium performance without the latest release price.

Key features:

Model: Galaxy S21 Ultra 5G
Display: 6.8-inch Dynamic AMOLED 2X, 1440 x 3200 pixels, 120Hz refresh rate
Processor: Exynos 2100 (Global) or Snapdragon 888 (US)
Camera: Quad-camera system with 108MP main sensor, 10MP periscope telephoto, 10MP telephoto, and 12MP ultra-wide
Connectivity: 5G capable for fast data transfer and low latency

Who is this for?

The Galaxy S21 Ultra 5G is ideal for tech enthusiasts, mobile photographers, or professionals who want a large, vibrant display and advanced camera capabilities. It suits users who need a high-performance device for demanding tasks like gaming, video editing, or photography.

Pros & Cons: Pros Cons Large, high-quality display with 120Hz refresh rate. Bulkier size may not suit users seeking a more compact device. Powerful camera system with high-resolution sensors. Battery life can vary depending on usage, especially with 120Hz refresh rate.
Why refurbished?

Opting for a refurbished Galaxy S21 Ultra 5G allows you to access a premium device at a more accessible price point. All devices from Back Market are tested and restored to meet strict quality standards. This sustainable choice helps reduce electronic waste. Learn more about our quality standards.

MPN: SM-G998UZKEXAA
Foldable: No
Serie: Samsung Galaxy S
Front camera: 40 megapixels
SAR head: 0.77
SIM card: Physical SIM + eSIM
Color (official name): Phantom Black
Manufacturer Ref.: SM-G998U
SAR body: 1.02
OS: Android
Carrier compatibility: Unlocked
Color: Black
Weight: 8 oz
Brand: Samsung
Storage: 256 GB
Resolution: 1440 x 3200
Memory (GB): 12 GB
Screen size (inches): 6.8
Main camera: 108 megapixels
Model: Galaxy S21 Ultra 5G
Last OS Compatibility: Yes
Network: 5G
Memory Card Slot: No
Screen type: Dynamic AMOLED 2X
Release Year: 2021

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Galaxy S21 Ultra 5G • UnlockedBlack • 256 GB • Physical SIM + eSIM

Galaxy S21 Ultra 5G • UnlockedBlack • 256 GB • Physical SIM + eSIM

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Customer reviews for Galaxy S21 Ultra 5G • Unlocked

Overall rating

Rating details

Reviews

Reviews

Christine P.

Billy H.

Philip H.

Wynsergs rave M.

Nikki H.

Joe M.

Olivia L.

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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