Galaxy S21 Ultra 5GDark Blue • 256 GB • Dual Physical SIM + eSIM

(6,537 reviews)

£263.80

before trade-in

Save £625.20

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

6,537 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

SM-G998B/DSManufacturer Ref
1.58SAR body
Phantom NavyColour (official name)
Dark BlueColour
Quadruple (4x)Camera Type
NoSD Card Slot
40 megapixelsFront camera
Galaxy S21 Ultra 5GModel
AndroidOS

The Galaxy S21 Ultra 5G is a flagship smartphone that continues to impress with its advanced features and performance. Launched in January 2021, it remains a top choice for users seeking a powerful device with exceptional camera capabilities and a stunning display.

Key features:

Release Date: January 2021
Display: 6.8-inch Dynamic AMOLED 2X, QHD+ resolution
Processor: Exynos 2100 (international) or Snapdragon 888 (USA)
Camera: Quad-camera system with 108MP main sensor, 12MP ultra-wide, and two 10MP telephoto lenses
Connectivity: 5G compatible for ultra-fast downloads and low-latency performance.

Who is this for?

The Galaxy S21 Ultra 5G is ideal for photography enthusiasts, gamers, and power users who demand high performance and versatility from their smartphones. It’s particularly well-suited for professionals who need a device that can handle multitasking and content creation with ease.

Pros & Cons:

Pros	Cons
Outstanding camera quality with versatile shooting options.	Large and heavy design may not be comfortable for all users.
Vibrant and immersive display with 120Hz refresh rate.	Premium price point compared to other models.

Why refurbished?

Choosing a refurbished Galaxy S21 Ultra 5G allows you to experience flagship features while being environmentally conscious. Back Market ensures each device is thoroughly tested and restored to excellent condition, providing you with a reliable smartphone. Learn more about our quality standards.

Manufacturer Ref: SM-G998B/DS
SAR body: 1.58
Colour (official name): Phantom Navy
Colour: Dark Blue
Camera Type: Quadruple (4x)
SD Card Slot: No
Front camera: 40 megapixels
Model: Galaxy S21 Ultra 5G
OS: Android
Foldable: No
Compatible with latest Update: Yes
Serie: Samsung Galaxy S
Brand: Samsung
Connector: USB-C
Screen size (in): 6.8
Carrier compatibility: Unlocked
SIM card: Dual Physical SIM + eSIM
Resolution: 1440 x 3200
SAR head: 0.71
Mobile network: 5G
Weight: 227 g
Main camera: 108 megapixels
Memory (GB): 12 GB
Storage: 256 GB
Screen type: Dynamic AMOLED 2X
Year of Release: 2021

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Galaxy S21 Ultra 5GDark Blue • 256 GB • Dual Physical SIM + eSIM

Galaxy S21 Ultra 5GDark Blue • 256 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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