Galaxy S21 Ultra 5G • UnlockedBlack • 512 GB • Physical SIM + eSIM

(1,367 reviews)

$399.99

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Free delivery by Jun 23 - 24

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Customer reviews for Galaxy S21 Ultra 5G • Unlocked

Overall rating

1,367 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
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

2.98 inWidth
Phantom BlackColor (official name)
512 GBStorage
0.35 inDepth
Physical SIM + eSIMSIM card
8 ozWeight
6.5 inHeight
2021Release Year
6.8Screen size (inches)

The Galaxy S21 Ultra 5G is a flagship smartphone introduced by Samsung in early 2021. It offers high-end specifications suitable for users seeking a powerful device with a large display and versatile camera system. This model is unlocked, making it compatible with various carriers and ideal for those who want flexibility in network choices.

Key features:

Display size: 6.8-inch Dynamic AMOLED 2X
Processor: Exynos 2100 (Global) or Snapdragon 888 (USA)
Camera system: Quad-camera setup with a 108MP main sensor
Storage capacity: 512GB
Connectivity: 5G capable for fast data speeds

Who is this for?

The Galaxy S21 Ultra 5G is suitable for tech enthusiasts, professionals, or content creators who require a premium device with a large, vibrant display and advanced photography features. It’s also ideal for users who prefer an unlocked phone for greater carrier flexibility.

Pros & Cons: Pros Cons Large, vibrant display with high refresh rate. Premium price compared to mid-range devices. Powerful Snapdragon 888 or Exynos 2100 chipset. Heavy and large, which may not suit all users. Versatile quad-camera system with 108MP main sensor. No headphone jack. Why refurbished?

Opting for a refurbished Galaxy S21 Ultra 5G offers a way to access a premium device at a more accessible price point. Each device undergoes thorough testing and quality checks to ensure functionality and condition. Back Market’s commitment to quality is outlined in our Quality Standards.

Width: 2.98 in
Color (official name): Phantom Black
Storage: 512 GB
Depth: 0.35 in
SIM card: Physical SIM + eSIM
Weight: 8 oz
Height: 6.5 in
Release Year: 2021
Screen size (inches): 6.8
Main camera: 108 megapixels
Front camera: 40 megapixels
Serie: Samsung Galaxy S
Network: 5G
Manufacturer Ref.: SM-G998
Model: Galaxy S21 Ultra 5G
Brand: Samsung
Memory Card Slot: No
OS: Android
Screen type: Dynamic AMOLED 2X
SAR body: 1.02
Foldable: No
Carrier compatibility: Unlocked
Resolution: 1440 x 3200
SAR head: 0.77
Last OS Compatibility: Yes
Memory (GB): 12 GB
Color: Black

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Galaxy S21 Ultra 5G • UnlockedBlack • 512 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.

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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