Galaxy S21 Ultra 5G 512GB - Dark Gray - Unlocked

Customer reviews for Galaxy S21 Ultra 5G

Overall rating

6,226 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
Blacklab M.
Verified purchase
Reviewed 27/08/2026, United Kingdom.
I orderedva premium level mobile. It looks and feels brand new. Arrived on time with plenty of tracking info. So far I am very pleased. This is the first time that I have purchased a refurbished item.
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Condition
Premium
Close to perfection. The body may have tiny micro-scratches. For items with screens, the screen will be flawless.
Purchased
19/08/2026
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
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
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

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

Durability
Overall performance
Camera
Screen quality

1.58SAR body
UnlockedCarrier compatibility
Physical SIM + eSIMSIM card
Phantom titaniumColour (official name)
2021Year of Release
Quadruple (4x)Camera Type
227 gWeight
5GMobile network
USB-CConnector

The Samsung Galaxy S21 Ultra 5G is a flagship smartphone that offers an impressive combination of advanced features and powerful performance. Released in January 2021, this model remains a top choice for users seeking high-end specifications and versatile functionality.

Key features:

Release Date: January 2021
Display: 6.8-inch Dynamic AMOLED 2X, QHD+ resolution
Processor: Exynos 2100 (International) / Snapdragon 888 (USA)
Camera: Quad-camera system with a 108MP main sensor
Connectivity: 5G compatible for ultra-fast download speeds.

Who is this for?

The Samsung Galaxy S21 Ultra 5G is perfect for professionals, content creators, and tech enthusiasts who require a powerful device for multitasking, photography, and media consumption. Its expansive display and advanced camera capabilities make it ideal for users who prioritize high-quality visuals and performance.

Pros & Cons:

Pros	Cons
Exceptional camera performance with 108MP sensor.	Large size may not suit all users.
Stunning AMOLED display with vibrant colours.	High price point compared to other models.

Why refurbished?

Choosing a refurbished Samsung Galaxy S21 Ultra 5G allows you to enjoy premium features while being environmentally conscious. Back Market ensures each device undergoes rigorous testing and quality checks, providing you with a reliable product. Learn more about our quality standards.

SAR body: 1.58
Carrier compatibility: Unlocked
SIM card: Physical SIM + eSIM
Colour (official name): Phantom titanium
Year of Release: 2021
Camera Type: Quadruple (4x)
Weight: 227 g
Mobile network: 5G
Connector: USB-C
Memory (GB): 16 GB
Brand: Samsung
Screen size (in): 6.8
SD Card Slot: No
Screen type: Dynamic AMOLED 2X
Front camera: 40 megapixels
Compatible with latest Update: Yes
Resolution: 1440 x 3200
Manufacturer Ref: SM-G998
SAR head: 0.71
Storage: 512 GB
Serie: Samsung Galaxy S
Colour: Dark Gray
OS: Android
Main camera: 108 megapixels
Model: Galaxy S21 Ultra 5G
Foldable: No

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Galaxy S21 Ultra 5G 512GB - Dark Gray - Unlocked

Customer reviews for Galaxy S21 Ultra 5G

Overall rating

Rating details

Reviews

Reviews

Javed S.

Blacklab M.

Peter H.

Aidas A.

Hakim A.

Stephanie W.

Deivids S.

Popular searches

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

Durability

Overall performance

Camera

Screen quality

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