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

(6,583 reviews)

£220.00

before trade-in

Save £929.00

Free delivery by 13 - 15 Jun

Restored professionally

Based on up to 100-points of inspection

Customer reviews for Galaxy S21 Ultra 5G

Overall rating

6,583 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

2,56SAR body part
1440 x 3200Resolution
USB-CConnector
128 GBStorage
Phantom BlackColour (official name)
Dual Physical SIM + eSIMSIM card
227 gWeight
108 megapixelsMain camera
16,15 cmHeight

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.

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

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

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.

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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