Galaxy S21 Ultra 5GBlack • 128 GB • Dual Physical SIM + eSIM

Name: Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Brand: Samsung
Price: 236.29 GBP
Availability: InStock
Rating: 4.29 (6619 reviews)

(6,619 reviews)

£236.29

before trade-in

Save £912.71

Free delivery by 29 - 30 Jul

Restored professionally

Based on up to 100-points of inspection

Customer reviews for Galaxy S21 Ultra 5G

Overall rating

6,619 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

40 megapixelsFront camera
12 GBMemory (GB)
7,56 cmWidth
SM-G998B/DSManufacturer Ref
5GMobile network
Galaxy S21 Ultra 5GModel
Dynamic AMOLED 2XScreen type
0,714SAR head
UnlockedCarrier compatibility

The Galaxy S21 Ultra 5G is a flagship smartphone from Samsung, released in January 2021. Known for its exceptional camera capabilities and high-end performance, this device is a great option for users looking for a powerful and versatile smartphone that can handle everything from photography to gaming.

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 108MP wide lens and 100x Space Zoom
Connectivity: 5G compatible for fast internet speeds.

Who is this for?

The Galaxy S21 Ultra 5G is ideal for photography enthusiasts, professionals, and power users who require a high-performance device. Its advanced camera features make it perfect for content creators, while its robust specifications cater to gamers and multitaskers.

Pros & Cons:

Pros	Cons
Outstanding camera quality with versatile shooting options.	Large and heavy design may not suit everyone.
High-resolution, vibrant display for an immersive experience.	Expensive accessories for optimal use, like the S Pen.

Why refurbished?

Choosing a refurbished Galaxy S21 Ultra 5G allows you to enjoy premium features while making an eco-conscious decision. Each device is thoroughly inspected and tested to meet high quality standards, ensuring reliability. Learn more about our quality standards.

Front camera: 40 megapixels
Memory (GB): 12 GB
Width: 7,56 cm
Manufacturer Ref: SM-G998B/DS
Mobile network: 5G
Model: Galaxy S21 Ultra 5G
Screen type: Dynamic AMOLED 2X
SAR head: 0,714
Carrier compatibility: Unlocked
Connector: USB-C
Main camera: 108 megapixels
OS: Android
Colour (official name): Phantom Black
Camera Type: Quadruple (4x)
Storage: 128 GB
Serie: Samsung Galaxy S
Foldable: No
Brand: Samsung
SAR body part: 2,56
Colour: Black
SD Card Slot: No
Resolution: 1440 x 3200
Depth: 0,89 cm
SAR body: 1,58
Screen size (in): 6.8
SIM card: Dual Physical SIM + eSIM
Weight: 227 g
Compatible with latest Update: Yes
Height: 16,15 cm
Year of Release: 2021

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Galaxy S21 Ultra 5GBlack • 128 GB • Dual Physical SIM + eSIM

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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.

Popular searches

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

Durability

Overall performance

Camera

Screen quality

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