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

(6,537 reviews)

£255.96

before trade-in

Save £633.04

Free delivery by 9 - 10 Jun

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
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
Andrea N.
Verified purchase
Reviewed 31/05/2026, United Kingdom.
my device was just as described, however within a few days it was clear it had a fault with mobile data. I contacted back market via help section. I received an identical phone the next day, and once my new phone had been updated I returned the faulty one. I was amazed how easy the issue I had was felt with and sorted. excellent service and the phone is working as it should.
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
19/05/2026
Keith H.
Verified purchase
Reviewed 25/05/2026, United Kingdom.
We had a device delivered and it wasn't working as it should, we were away on holiday and it turned itself off and wouldn't restart. I emailed Back market and they sent out a replacement within 24 hours. Excellent customer service, we will certainly recommend and use them again.
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
14/05/2026
Michelle G.
Verified purchase
Reviewed 24/05/2026, United Kingdom.
First time I’ve ever bought from Back Market & have to honestly say the service was fantastic. The phone I got was in excellent condition, the delivery service was quick and can’t fault the company what so ever. Will definitely recommend to friends & will be using this company for my next purchase. Thank you again for amazing service.
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
09/05/2026

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

Durability
Overall performance
Camera
Screen quality

SM-G998B/DSManufacturer Ref
YesCompatible with latest Update
Phantom NavyColour (official name)
Galaxy S21 Ultra 5GModel
40 megapixelsFront camera
Dynamic AMOLED 2XScreen type
12 GBMemory (GB)
1440 x 3200Resolution
256 GBStorage

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

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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.

Hakim A.

Stephanie W.

Deivids S.

Andrea N.

Keith H.

Michelle G.

Popular searches

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

Durability

Overall performance

Camera

Screen quality

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