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Proudly refurbished by Stock Must Go Ltd (United Kingdom)
Comes with
Compatible charging cable
3,686 verified reviews in the last 24 months.
Aidas A.
Purchased on the 11 March 2025
Verified purchaseI ordered samsung s21 ultra,and it comes in very good condition. There are no scratches on the phone at all. It works like a new one . I would recommend to everyone it's better to buy refurbished on a half price than pay full price at store for a new one.
Reviewed in United Kingdom on 28 April 2025
Galaxy S21 Ultra 5G 512GB - Black - UnlockedAseela A.
Purchased on the 28 October 2024
Verified purchaseI'm going to be fully honest. For a refurbished phone, the quality is absolutely surreal. No one could tell the difference between this excellent quality phone from back market and a brand new phone. I am completely satisfied and hope to shop again on this website. Back market is seriously outstanding from other stores, easy 5 stars, completely thrilled about the quality.
Reviewed in United Kingdom on 11 May 2025
Galaxy S21 Ultra 5G 128GB - Black - UnlockedPaul L.
Purchased on the 22 October 2024
Verified purchaseNeeding a new phone and the cost is too much. Well look no further than Black Market. Ive just purchased a refurbished S21 Ultra 5G 128GB from them. I went for their good option and if this is their good option, goodness knows what you get for their best option. This phone was unmarked, charged to 80% out of the box, came with a case and lead. It`s fast, it`s reliable and it ticks all the boxes I could want from a phone. Excellent service from them. Know where I will be heading next time I require any communication device.
Reviewed in United Kingdom on 8 May 2025
Galaxy S21 Ultra 5G 128GB - Black - UnlockedJaved S.
Purchased on the 23 March 2025
Verified purchaseOrdered 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.
Reviewed in United Kingdom on 8 May 2025
Galaxy S21 Ultra 5G 256GB - Silver - UnlockedAlexandra M.
Purchased on the 14 February 2025
Verified purchaseWell it takes a bit of getting used to jumping from S10 to S21 ultra. It was a recommendation from my son. Can't complain as at least I know the basics of Samsung Galaxy, as it's my favourite model. And I now have far more extras. Also I have no complaints regarding the reconditioning of the phone, saving a considerable amount of money & delivery from Back Market.
Reviewed in United Kingdom on 29 April 2025
Galaxy S21 Ultra 5G 128GB - Silver - UnlockedLorraine H.
Purchased on the 12 October 2024
Verified purchase1st time I have used this company for refurbished phones very happy with Samsung galaxy 21 ultra , would defo do this again alot cheaper than buying brand new 😀
Reviewed in United Kingdom on 25 April 2025
Galaxy S21 Ultra 5G 128GB - Black - UnlockedAbimbola O.
Purchased on the 31 March 2024
Verified purchaseThis is a fantastic phone and I totally recommend it. I was initially skeptical about buying a refurbished phone but I saw all the positive reviews and decided to give it a shot. I went for the "good" option just to be safe and I was totally satisfied with my purchase. The phone looks new with an unnoticeable scratch at the back. Other than that, it is totally worth it. I'm enjoying the phone. Thumbs up to the Back Market for their excellent customer service. I will surely come back for more. 😊
Reviewed in United Kingdom on 3 April 2025
Galaxy S21 Ultra 5G 128GB - Silver - UnlockedHere’s what you help prevent on average by choosing a reborn smartphone over a brand new one.
That’s like driving an old banger from London to Edinburgh and back.
That’s around the weight of a baseball.
That's like 20 dogs digging in your yard for a week.
That's like running a faucet for 3 days
BlackColour
128 GBStorage
12 GBMemory
Galaxy S21 Ultra 5GModel
AndroidOS
NoRetro tech
Dynamic AMOLED 2XScreen type
USB-CConnector
40 megapixelsFront camera
The Galaxy S21 Ultra 5G is a premium smartphone that continues to impress with its top-tier specifications and features. Launched in January 2021, it remains a strong contender for those seeking a high-performance device with advanced capabilities.
Key features:The Galaxy S21 Ultra 5G is ideal for professionals, photographers, and tech enthusiasts who demand a robust camera system and a stunning display for media consumption. It’s also suitable for gamers and multitaskers looking for a device that can handle demanding applications smoothly.
Pros & Cons:Pros | Cons |
---|---|
Exceptional camera capabilities, including 100x Space Zoom. | Size and weight may be cumbersome for some users. |
Stunning display with vibrant colours and high resolution. | Premium price point compared to other smartphones. |
Choosing a refurbished Galaxy S21 Ultra 5G allows you to enjoy flagship features without the new device price tag. Back Market ensures all refurbished devices undergo strict quality checks to guarantee reliability and performance. Learn more about our quality standards.
Colour | Black |
Storage | 128 GB |
Memory | 12 GB |
Model | Galaxy S21 Ultra 5G |
OS | Android |
Retro tech | No |
Screen type | Dynamic AMOLED 2X |
Connector | USB-C |
Front camera | 40 megapixels |
Company name | Samsung Electronics |
Camera Type | Quadruple (4x) |
Series | Samsung Galaxy S |
Company email address | support@samsung.com |
Company postal address | Samsung House, 1000 Hillswood Drive, Chertsey, Surrey, KT16 0PS, UK |
SIM card | Physical SIM + eSIM |
Main camera | 108 megapixels |
Colour (official name) | Phantom Black |
SD Card Slot | No |
Foldable | No |
Compatible with latest Update | Yes |
Manufacturer Ref | SM-G998B |
Network | 5G |
Resolution | 1440 x 3200 |
SAR body | 1.58 |
SAR head | 0.71 |
Screen size (in) | 6.8 |
Carrier compatibility | Unlocked |
Year of Release | 2021 |
Brand | Samsung |
Weight | 227 g |