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Galaxy S21 Ultra 5G

£193.32
before trade-in
Save £1,122.68


Free delivery by 15 May - 16 May

All devices are restored professionally based on a 25-point inspection

  • Buttons
  • SIM and/or memory card reader
  • Data deletion
  • Chargers and/or cables
  • Unlocking
  • GPS and/or positioning system
  • Cameras
  • External sensors
  • Biometric sensors
  • WiFi and Bluetooth
  • IMEI serial number
  • Oxidation
  • Flash and indicator lights
  • Mics and speakers
  • Input and output ports
  • Phone carrier
  • Battery health
  • Mechanical parts
  • Parts compatibility
  • Screen
  • Other features specific to this device

Ta-da!

Galaxy S21 Ultra 5G 128GB - Black - Unlocked
Galaxy S21 Ultra 5G
FairStandard battery128 GBPhysical SIM + eSIMBlack
£193.32
before trade-in
Save £1,122.68

Proudly refurbished by Stock Must Go Ltd (United Kingdom)

Free delivery by 15 May - 16 May

Comes with

Compatible charging cable

Galaxy S21 Ultra 5G: customer reviews

4.3/5

3,686 verified reviews in the last 24 months.

  • A

    Aidas A.

    Purchased on the 11 March 2025

    Verified purchase
    5/5

    I 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 - Unlocked
  • A

    Aseela A.

    Purchased on the 28 October 2024

    Verified purchase
    4.9/5

    I'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 - Unlocked
  • P

    Paul L.

    Purchased on the 22 October 2024

    Verified purchase
    5/5

    Needing 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 - Unlocked
  • J

    Javed S.

    Purchased on the 23 March 2025

    Verified purchase
    5/5

    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.

    Reviewed in United Kingdom on 8 May 2025

    Galaxy S21 Ultra 5G 256GB - Silver - Unlocked
  • A

    Alexandra M.

    Purchased on the 14 February 2025

    Verified purchase
    4/5

    Well 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 - Unlocked
  • L

    Lorraine H.

    Purchased on the 12 October 2024

    Verified purchase
    5/5

    1st 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 - Unlocked
  • A

    Abimbola O.

    Purchased on the 31 March 2024

    Verified purchase
    4.4/5

    This 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 - Unlocked
See all 3,686 reviews

Reborn vs. brand new

Here’s what you help prevent on average by choosing a reborn smartphone over a brand new one.

77.3 kg of carbon

That’s like driving an old banger from London to Edinburgh and back.

6.3 oz of e-waste

That’s around the weight of a baseball.

537.1 lbs of raw materials

That's like 20 dogs digging in your yard for a week.

77,000 litres of water

That's like running a faucet for 3 days

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


  • Durability

  • Overall performance

  • Camera

  • Screen quality

  • 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:
  • Release Date: January 2021
  • Display: 6.8-inch Dynamic AMOLED 2X, QHD+ resolution
  • Processor: Exynos 2100 or Snapdragon 888 (depending on region)
  • Camera: Quad-camera system with 108MP wide lens
  • 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 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.

Why refurbished?

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.

Galaxy S21 Ultra 5G 128GB - Black - Unlocked
ColourBlack
Storage128 GB
Memory12 GB
ModelGalaxy S21 Ultra 5G
OSAndroid
Retro techNo
Screen typeDynamic AMOLED 2X
ConnectorUSB-C
Front camera40 megapixels
Company nameSamsung Electronics
Camera TypeQuadruple (4x)
SeriesSamsung Galaxy S
Company email addresssupport@samsung.com
Company postal addressSamsung House, 1000 Hillswood Drive, Chertsey, Surrey, KT16 0PS, UK
SIM cardPhysical SIM + eSIM
Main camera108 megapixels
Colour (official name)Phantom Black
SD Card SlotNo
FoldableNo
Compatible with latest UpdateYes
Manufacturer RefSM-G998B
Network5G
Resolution1440 x 3200
SAR body1.58
SAR head0.71
Screen size (in)6.8
Carrier compatibilityUnlocked
Year of Release2021
BrandSamsung
Weight227 g
  • 1-year minimum warranty
  • Free delivery on all items
  • Free 30-day returns
  • Excellent customer support