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

(6,226 reviews)

£244.00

before trade-in

Save £1,256.00

Free delivery by 10 - 11 Jun

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Based on up to 100-points of inspection

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

Jodie K.
Verified purchase
Reviewed 08/07/2025, United Kingdom.
So 1st phone I ordered took a while to come but it was ordered late on a Friday and it was a bank holiday wkend... When it came, on first glance it looked amazing for a fair condition phone, but then I realised the back was coming off and it looked to have an ott amount of adhesive inside it. I was gutted because other than that it was an amazing phone in excellent condition!! And, I was desperate for a phone!! . So then i have to send it back and wait for the refund before I could get another.. It was a total pain in the arse. So I'm knocking a star off purely because someone should have checked the phone better before they sent it! But due to how good the phone was (not counting the back hanging off), the prices, warranty, straightforward refund etc etc and most of all the tons of good reviews compared to bad ones., I decided I would give back market another go... And I am sooo glad I did.. Got an awesome phone for the price, got fair condition and it's like brand new!! Came the next day as well!! I'm well chuffed!! 😁😁😁 (would have been 5stars!!)
Galaxy S21 Ultra 5G 256GB - Silver - Unlocked
Galaxy S21 Ultra 5G 256GB - Silver - Unlocked
Condition
Fair
Signs of wear. The body may have a few visible scratches and dents. Items with screens may have light scratches.
Purchased
25/06/2025
Paul C.
Verified purchase
Reviewed 01/05/2026, United Kingdom.
was for my granddaughter, as she had gone off i phones . she is very happy with it and staying with samsung now .
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
17/04/2026
Steven T.
Verified purchase
Reviewed 29/04/2026, United Kingdom.
Brought for my son. Arrived very quick and in excellent condition (ordered fair condition) no visible marks on the phone. Son is loving the phone and means I can save money on his contract
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
10/04/2026
Keith W.
Verified purchase
Reviewed 13/04/2026, United Kingdom.
Brilliant service , fast transaction and delivery. Very pleased with my phone , it is like new , I’m a very satisfied customer.
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
31/03/2026
Edward P.
Verified purchase
Reviewed 27/07/2025, United Kingdom.
First time buying on back market, i ordered Samsung Galaxy S21 ultra in fair condition, but the phone comes in very good condition, very clean, the shipping was supposed to take 4 days but i received the parcel the next day after my order. looking forward in purchasing more
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Condition
Fair
Signs of wear. The body may have a few visible scratches and dents. Items with screens may have light scratches.
Purchased
25/07/2025
Mohammed saifur R.
Verified purchase
Reviewed 18/06/2025, United Kingdom.
Honest review. Although it is refurbished, it looks and feels like ive purchased a brand new phone... it also arrived 2 days earlier than expected.
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
13/06/2025
Joshua F.
Verified purchase
Reviewed 01/04/2025, United Kingdom.
finally a decent phone in back market!! I have bought 3 phones from this website and so far all of them have been defective or using non-genuine parts, however with this one, my phone came with a real genuine screen! (rare for most refurbs these days). it was packaged well and delivered quickly too. 5*
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
28/03/2025

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

Durability
Overall performance
Camera
Screen quality

1.58SAR body
12 GBMemory (GB)
5GMobile network
Quintuple (5x)Camera Type
2021Year of Release
Dynamic AMOLED 2XScreen type
227 gWeight
Dark BlueColour
USB-CConnector

The Galaxy S21 Ultra 5G is a flagship smartphone from Samsung, known for its impressive camera capabilities and high-end performance. Launched in January 2021, it remains a top choice for users seeking a premium device that excels in photography and multitasking.

Key features:

Release Date: January 2021
Display: 6.8-inch Dynamic AMOLED 2X, QHD+ resolution
Processor: Exynos 2100 (or Snapdragon 888, depending on the region)
Camera: Quad-camera setup with 108MP wide lens, 12MP ultra-wide, and dual telephoto lenses
Connectivity: 5G compatible ensuring ultra-fast downloads and low-latency performance.

Who is this for?

The Galaxy S21 Ultra 5G is ideal for professionals, photographers, and tech enthusiasts who demand the best in camera quality and performance. It suits users who often multitask and enjoy high-resolution media playback, making it great for both work and entertainment.

Pros & Cons:

Pros	Cons
Exceptional camera quality with versatile shooting options.	Large size may be cumbersome for some users.
Vibrant and high-resolution display for immersive viewing.	Expensive accessories may be needed to maximize functionality.

Why refurbished?

Choosing a refurbished Galaxy S21 Ultra 5G is an eco-conscious decision that allows you to enjoy premium features without the environmental impact of new production. Each device is thoroughly tested and certified for quality by Back Market. Learn more about our quality standards.

SAR body: 1.58
Memory (GB): 12 GB
Mobile network: 5G
Camera Type: Quintuple (5x)
Year of Release: 2021
Screen type: Dynamic AMOLED 2X
Weight: 227 g
Colour: Dark Blue
Connector: USB-C
SIM card: Dual Physical SIM + eSIM
Compatible with latest Update: Yes
Manufacturer Ref: SM-G998B
Colour (official name): Phantom Navy
SD Card Slot: No
Main camera: 108 megapixels
Foldable: No
Serie: Samsung Galaxy S
Carrier compatibility: Unlocked
Screen size (in): 6.8
SAR head: 0.71
Brand: Samsung
Front camera: 40 megapixels
Storage: 128 GB
Resolution: 1440 x 3200
OS: Android
Model: Galaxy S21 Ultra 5G

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

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

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Customer reviews for Galaxy S21 Ultra 5G

Overall rating

Rating details

Reviews

Reviews

Jodie K.

Paul C.

Steven T.

Keith W.

Edward P.

Mohammed saifur R.

Joshua F.

Popular searches

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

Durability

Overall performance

Camera

Screen quality

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