Galaxy S21 Ultra 5GBlack • 256 GB • Physical SIM + eSIM

(6,577 reviews)

£266.00

before trade-in

Save £733.00

Free delivery by 4 - 5 Jun

Restored professionally

Based on up to 100-points of inspection

Customer reviews for Galaxy S21 Ultra 5G

Overall rating

6,577 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

YesCompatible with latest Update
Physical SIM + eSIMSIM card
Phantom BlackColour (official name)
1440 x 3200Resolution
Samsung Galaxy SSerie
256 GBStorage
NoFoldable
AndroidOS
40 megapixelsFront camera

The Galaxy S21 Ultra 5G is a high-end smartphone that combines cutting-edge technology with a premium design. Launched in January 2021, it remains a top choice for those seeking exceptional performance and versatile camera capabilities.

Key features:

Display: 6.8-inch Dynamic AMOLED 2X, QHD+ resolution
Processor: Exynos 2100 (International) / Snapdragon 888 (USA)
Camera: Quad-camera system with a 108MP wide lens, 12MP ultra-wide, and dual 10MP telephoto lenses
Connectivity: 5G compatible for ultra-fast downloads and streaming
Operating System: Ships with Android 11, upgradable to the latest version

Who is this for?

The Galaxy S21 Ultra 5G is ideal for professionals, photographers, and tech enthusiasts who require a powerful device for multitasking and high-quality photography. It’s also a great option for users who enjoy media consumption on a large, vibrant display.

Pros & Cons:

Pros	Cons
Exceptional camera quality with versatile shooting options.	Large size may not be suitable for all users.
Stunning display with vibrant colours and high refresh rate.	Premium build can be prone to fingerprints.

Why refurbished?

Choosing a refurbished Galaxy S21 Ultra 5G allows you to access top-tier features while making an eco-conscious choice. Each device is rigorously tested to meet Back Market’s quality standards, ensuring reliability. Learn more about our quality standards.

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

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Galaxy S21 Ultra 5GBlack • 256 GB • Physical SIM + eSIM

Galaxy S21 Ultra 5GBlack • 256 GB • 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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