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Galaxy S21 Ultra 5G
- Fair
- 256 GB
- Dual Physical SIM + eSIM
- Black
£210.00
before trade-in
applies (starting at £0.49)
Save £1,040.00
Proudly refurbished by BEST4TECH
Free delivery by 29 - 30 Oct
Express delivery by 28-29 Oct from £5.00
Comes with
Compatible charging cable
Often bought together
Galaxy S21 Ultra 5G
Black • 256 GB • Dual Physical SIM + eSIM
Refurbished price:£210.00
£1,250.00 newVersus £1,250.00 new
Total price: £231.99
These items might be sold and delivered by different sellers.
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Pairs well with
- 4.3/5 (25)Brand new
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Customer reviews for Galaxy S21 Ultra 5G
Overall rating
4.3/54.3/56,670 verified reviewsRating 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
Reviews
Javed S.
Verified purchaseReviewed 07/04/2025, United Kingdom.
5/5Ordered 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
See itemCondition
Good
Purchased
23/03/2025
Blacklab M.
Verified purchaseReviewed 27/08/2026, United Kingdom.
4.8/5I orderedva premium level mobile. It looks and feels brand new. Arrived on time with plenty of tracking info. So far I am very pleased. This is the first time that I have purchased a refurbished item.
Galaxy S21 Ultra 5G 128GB - Black - Unlocked
See itemCondition
Premium
Purchased
19/08/2026
Jamal B.
Verified purchaseReviewed 22/08/2025, United Kingdom.
4.5/5I’m really happy with my purchase – absolutely worth it! The condition was even better than described on the website. The only small thing I’ve noticed is that the screen response feels slightly slower compared to my old S21 Ultra in similar condition, but overall I’m very satisfied. It's a silver one just I coverd the camera wiht a black case! Definitely recommend Back Market :)
Galaxy S21 Ultra 5G 128GB - Silver - Unlocked
See itemCondition
Good
Purchased
04/08/2025
Peter H.
Verified purchaseReviewed 14/07/2026, United Kingdom.
5/5was 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
See itemCondition
Good
Purchased
06/07/2026
Hakim A.
Verified purchaseReviewed 13/05/2026, United Kingdom.
4.5/5It 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
See itemCondition
Good
Purchased
25/04/2026
Laura B.
Verified purchaseReviewed 02/06/2025, United Kingdom.
5/5was the first time coming across this online store, I was very sceptical as the prices were very low so I carefully read every review and edited to purchase the s21 ultra. It arrived less then 48 hours later with clear communication on tracking and delivery, opened the box and the phone was in prestige condition basically brand new will never be using a highstreet store for phones etc again this is definitely the new go to. I oped for the fair condition the cheapest one so didn't expect the service and item I received. thankyou back market
Galaxy S21 Ultra 5G 256GB - Black - Unlocked
See itemCondition
Fair
Purchased
19/05/2025
Richard M.
Verified purchaseReviewed 15/06/2026, United Kingdom.
5/5unfortunately 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
See itemCondition
Good
Purchased
01/06/2026
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Everything you ever wanted to know about the Galaxy S21 Ultra 5G
Durability
Overall performance
Camera
Screen quality
256 GBStorage
16,15 cmHeight
Samsung Galaxy SSerie
NoSD Card Slot
108 megapixelsMain camera
NoFoldable
0,714SAR head
SamsungBrand
5GMobile network
The Galaxy S21 Ultra 5G is a flagship smartphone from Samsung that continues to impress with its advanced features and powerful performance. Released in January 2021, this device is designed for users who demand the best in photography, display quality, and overall functionality.
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 a 108MP main sensor and 100x Space Zoom
- Connectivity: 5G compatible for ultra-fast downloads and low-latency performance.
The Galaxy S21 Ultra 5G is ideal for professionals, photographers, and tech enthusiasts who require a high-performance smartphone with exceptional camera capabilities and a stunning display. Its versatility makes it suitable for both work and play, providing an immersive experience for content consumption and creation.
Pros & Cons:| Pros | Cons |
|---|---|
| Exceptional camera performance with versatile shooting options. | Large and heavy compared to other smartphones. |
| Stunning display quality with vibrant colours and high resolution. | Premium price point for flagship features. |
Why refurbished?
Choosing a refurbished Galaxy S21 Ultra 5G allows you to experience top-tier technology while being eco-conscious. Back Market ensures that all refurbished devices undergo rigorous testing for quality and functionality. Learn more about our quality standards.
- Storage
- 256 GB
- Height
- 16,15 cm
- Serie
- Samsung Galaxy S
- SD Card Slot
- No
- Main camera
- 108 megapixels
- Foldable
- No
- SAR head
- 0,714
- Brand
- Samsung
- Mobile network
- 5G
- Weight
- 227 g
- Width
- 7,56 cm
- Screen type
- Dynamic AMOLED 2X
- SIM card
- Dual Physical SIM + eSIM
- Resolution
- 1440 x 3200
- Screen size (in)
- 6.8
- SAR body
- 1,58
- Camera Type
- Quadruple (4x)
- SAR body part
- 2,56
- Compatible with latest Update
- Yes
- Front camera
- 40 megapixels
- Depth
- 0,89 cm
- Carrier compatibility
- Unlocked
- Connector
- USB-C
- Colour (official name)
- Phantom black
- Memory (GB)
- 12 GB
- Year of Release
- 2021
- OS
- Android
- Model
- Galaxy S21 Ultra 5G
- Colour
- Black
- Manufacturer Ref
- SM-G998B/DS
Galaxy S21 Ultra 5G
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