Galaxy S21 Ultra 5G 256GB - Black - Unlocked

Customer reviews for Galaxy S21 Ultra 5G

Overall rating

6,600 verified reviews

Rating details

Accessories
4.1/5
Appearance
4.4/5
Battery
4.1/5
Lens & Camera
4.5/5
Overall performance
4.3/5
Packaging
4.4/5
Shipping
4.6/5

Reviews

Javed S.
Verified purchase
Reviewed 07/04/2025, United Kingdom.
Ordered a "Good" quality Samsung Galaxy S21 Ultra 5g phone and surprised as its almost like a brand new phone apart from a few cosmetic dints which were expected I suppose. Still to find out how battery performs over time but my wife is quiet impressed with the phone. Would definitely buy another phone from here as they've kept the word on quality of the phone. Keep up the good work and help the planet.
Galaxy S21 Ultra 5G 256GB - Silver - Unlocked
Galaxy S21 Ultra 5G 256GB - Silver - Unlocked
Condition
Good
Light signs of wear. The body may have light micro-scratches. For items with screens, the screen will have no scratches.
Purchased
23/03/2025
Peter H.
Verified purchase
Reviewed 14/07/2026, United Kingdom.
was very pleased with my phone Samsung galaxy S21 ultra. Condition was very good and battery life seems to be excellent far exceeding my expectation as suppliers description was good. The actual purchase was straight forward and delivery was very timely . Could not be more pleased
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Condition
Good
Light signs of wear. The body may have light micro-scratches. For items with screens, the screen will have no scratches.
Purchased
06/07/2026
Hakim A.
Verified purchase
Reviewed 13/05/2026, United Kingdom.
It is so far the best experience I had with a refurbished phone it is absolutely stunning the quality is Immaculate and the service has been fast Safe and efficient. I have recommended Back Market to my friend who bought a phone for his wife I also highly recommend this seller to anyone who wants a very good phone at a fraction of the price.
Galaxy S21 Ultra 5G 128GB - Silver - Unlocked
Galaxy S21 Ultra 5G 128GB - Silver - Unlocked
Condition
Good
Light signs of wear. The body may have light micro-scratches. For items with screens, the screen will have no scratches.
Purchased
25/04/2026
Stephanie W.
Verified purchase
Reviewed 15/04/2026, United Kingdom.
Absolutely brilliant phone. I am very happy with my purchase. Samsung galaxy s21 ultra. The phone arrived in perfect condition and although I requested a phone in" good condition" I can't tell the difference from a brand new one. I would highly recommend Back market to anyone.
Galaxy S21 Ultra 5G 256GB - Dark Blue - Unlocked
Galaxy S21 Ultra 5G 256GB - Dark Blue - Unlocked
Condition
Good
Light signs of wear. The body may have light micro-scratches. For items with screens, the screen will have no scratches.
Purchased
11/04/2026
Deivids S.
Verified purchase
Reviewed 04/03/2026, United Kingdom.
Much better than previous phone, this time rear camera was refurbished right and auto focused without the onbnoxious manual tapping. Battery is solid so far and minimal scratches all for a good price :)
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
19/02/2026
Aidas A.
Verified purchase
Reviewed 27/03/2025, United Kingdom.
I ordered samsung s21 ultra,and it comes in very good condition. There are no scratches on the phone at all. It works like a new one . I would recommend to everyone it's better to buy refurbished on a half price than pay full price at store for a new one.
Galaxy S21 Ultra 5G 512GB - Black - Unlocked
Galaxy S21 Ultra 5G 512GB - Black - Unlocked
Condition
Premium
Close to perfection. The body may have tiny micro-scratches. For items with screens, the screen will be flawless.
Purchased
11/03/2025
Richard M.
Verified purchase
Reviewed 15/06/2026, United Kingdom.
unfortunately I have locked myself out of the phone. I have given it to technicians and am waiting for them to get me back into it. as soon as I get it back I will transfer my data and send it on to you. I think that will be the middle of next week
Galaxy S21 Ultra 5G 128GB - Silver - Unlocked
Galaxy S21 Ultra 5G 128GB - Silver - Unlocked
Condition
Good
Light signs of wear. The body may have light micro-scratches. For items with screens, the screen will have no scratches.
Purchased
01/06/2026

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

Durability
Overall performance
Camera
Screen quality

Phantom BlackColour (official name)
NoSD Card Slot
2021Year of Release
256 GBStorage
5GMobile network
Quintuple (5x)Camera Type
12 GBMemory (GB)
1.58SAR body
108 megapixelsMain camera

The Galaxy S21 Ultra 5G is a high-end smartphone that combines cutting-edge technology with a premium design. Launched in January 2021, it remains a top choice for those seeking exceptional performance and versatile camera capabilities.

Key features:

Display: 6.8-inch Dynamic AMOLED 2X, QHD+ resolution
Processor: Exynos 2100 (International) / Snapdragon 888 (USA)
Camera: Quad-camera system with a 108MP wide lens, 12MP ultra-wide, and dual 10MP telephoto lenses
Connectivity: 5G compatible for ultra-fast downloads and streaming
Operating System: Ships with Android 11, upgradable to the latest version

Who is this for?

The Galaxy S21 Ultra 5G is ideal for professionals, photographers, and tech enthusiasts who require a powerful device for multitasking and high-quality photography. It’s also a great option for users who enjoy media consumption on a large, vibrant display.

Pros & Cons:

Pros	Cons
Exceptional camera quality with versatile shooting options.	Large size may not be suitable for all users.
Stunning display with vibrant colours and high refresh rate.	Premium build can be prone to fingerprints.

Why refurbished?

Choosing a refurbished Galaxy S21 Ultra 5G allows you to access top-tier features while making an eco-conscious choice. Each device is rigorously tested to meet Back Market’s quality standards, ensuring reliability. Learn more about our quality standards.

Colour (official name): Phantom Black
SD Card Slot: No
Year of Release: 2021
Storage: 256 GB
Mobile network: 5G
Camera Type: Quintuple (5x)
Memory (GB): 12 GB
SAR body: 1.58
Main camera: 108 megapixels
Resolution: 1440 x 3200
OS: Android
SAR head: 0.71
Compatible with latest Update: Yes
Colour: Black
Screen type: Dynamic AMOLED 2X
Brand: Samsung
Connector: USB-C
SIM card: Physical SIM + eSIM
Manufacturer Ref: SM-G998B
Screen size (in): 6.8
Carrier compatibility: Unlocked
Serie: Samsung Galaxy S
Foldable: No
Front camera: 40 megapixels
Weight: 227 g
Model: Galaxy S21 Ultra 5G

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Galaxy S21 Ultra 5G 256GB - Black - Unlocked

Customer reviews for Galaxy S21 Ultra 5G

Overall rating

Rating details

Reviews

Reviews

Javed S.

Peter H.

Hakim A.

Stephanie W.

Deivids S.

Aidas A.

Richard M.

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

Durability

Overall performance

Camera

Screen quality

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