Galaxy S21 Ultra 5G

(6,591 reviews)

£191.99

before trade-in

Save £1,124.01

Free delivery by 18 - 19 Jun

Restored professionally

Based on up to 100-points of inspection

Often bought together

Galaxy S21 Ultra 5G

Black • 128 GB • Physical SIM + eSIM

Refurbished price:£191.99

Versus £1,316.00 new

Case Galaxy S21 Ultra 5G and 2 protective screens - TPU - Transparent

Refurbished price:£23.99

Total price: £215.98

These items might be sold and delivered by different sellers.

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Customer reviews for Galaxy S21 Ultra 5G

Overall rating

6,591 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
See item
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
See item
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
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
See item
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
Richard M.
Verified purchase
Reviewed 15/06/2026, United Kingdom.
unfortunately 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
Galaxy S21 Ultra 5G 128GB - Silver - Unlocked
See item
Condition
Good
Light signs of wear. The body may have light micro-scratches. For items with screens, the screen will have no scratches.
Purchased
01/06/2026
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
See item
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
See item
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
See item
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

Quadruple (4x)Camera Type
40 megapixelsFront camera
Dynamic AMOLED 2XScreen type
SamsungBrand
NoSD Card Slot
BlackColour
SM-G998BManufacturer Ref
5GMobile network
Galaxy S21 Ultra 5GModel

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.

Camera Type: Quadruple (4x)
Front camera: 40 megapixels
Screen type: Dynamic AMOLED 2X
Brand: Samsung
SD Card Slot: No
Colour: Black
Manufacturer Ref: SM-G998B
Mobile network: 5G
Model: Galaxy S21 Ultra 5G
Weight: 227 g
SIM card: Physical SIM + eSIM
Year of Release: 2021
SAR body: 1.58
Compatible with latest Update: Yes
Storage: 128 GB
Colour (official name): Phantom Black
Memory (GB): 12 GB
Serie: Samsung Galaxy S
SAR head: 0.71
Main camera: 108 megapixels
OS: Android
Carrier compatibility: Unlocked
Screen size (in): 6.8
Foldable: No
Connector: USB-C
Resolution: 1440 x 3200

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Galaxy S21 Ultra 5G

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Customer reviews for Galaxy S21 Ultra 5G

Overall rating

Rating details

Reviews

Reviews

Javed S.

Hakim A.

Deivids S.

Richard M.

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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