Galaxy S21 5GGrey • 128 GB • Physical SIM + eSIM

Name: Galaxy S21 5G 128GB - Grey - Unlocked
Brand: Samsung
Price: 172.00 GBP
Availability: InStock
Rating: 4.3 (19198 reviews)

(19,198 reviews)

£172.00

before trade-in

Save £854.00

Free delivery by 8 - 10 Aug

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Based on up to 100-points of inspection

Customer reviews for Galaxy S21 5G

Overall rating

19,198 verified reviews

Rating details

Accessories
4.1/5
Appearance
4.5/5
Battery
4/5
Lens & Camera
4.5/5
Overall performance
4.2/5
Packaging
4.5/5
Shipping
4.6/5

Reviews

Al B.
Verified purchase
Reviewed 17/04/2026, United Kingdom.
Phone is in excellent condition, much better than i was expecting, I can't find a single scratch on the phone, working great, came well packaged, quick shipping to Ireland, I highly recommend this site 🌟🌟🌟🌟🌟
Galaxy S21 5G 128GB - Purple - Unlocked
Galaxy S21 5G 128GB - Purple - Unlocked
Condition
Fair
Signs of wear. The body may have a few visible scratches and dents. Items with screens may have light scratches.
Purchased
14/04/2026
Kane G.
Verified purchase
Reviewed 21/07/2026, United Kingdom.
considering it's fair condition it's still in great condition no problems no scratches or minor damage im amazed by the s21 Samsung next step is to sort out coverage option as i don't want damage to the phone as im very clumsy sometimes great item im very thankful
Galaxy S21 5G 128GB - Grey - Unlocked
Galaxy S21 5G 128GB - Grey - Unlocked
Condition
Fair
Signs of wear. The body may have a few visible scratches and dents. Items with screens may have light scratches.
Purchased
13/07/2026
Denise R.
Verified purchase
Reviewed 18/06/2026, United Kingdom.
phone was in great condition looked like a new phone and I liked the colour only draw back was after setting it up had to give it at least 8 software updates now phone is working like it should but I would still buy another phone from this company if I needed one their alot cheaper than some of these shops that sell used phones
Galaxy S21 5G 128GB - Purple - Unlocked
Galaxy S21 5G 128GB - Purple - 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
02/06/2026
Jenny B.
Verified purchase
Reviewed 08/06/2026, United Kingdom.
Condition said it was fair but its near on perfect. Bought for my mum who is in her 80s, easy for her to navigate her way round and easy for her to use. This is the 3rd time buying from this site, wouldn't buy phones from anywhere else now. Thankyou. 😀
Galaxy S21 5G 128GB - Grey - Unlocked
Galaxy S21 5G 128GB - Grey - Unlocked
Condition
Fair
Signs of wear. The body may have a few visible scratches and dents. Items with screens may have light scratches.
Purchased
24/05/2026
Matthew S.
Verified purchase
Reviewed 26/04/2026, United Kingdom.
I was a little nervous to order a refurbished phone but I've gotta say this honestly feels like brand new! There's only minor signs of wear and tear on the main body but other than that it's pretty much perfect!
Galaxy S21 5G 128GB - Grey - Unlocked
Galaxy S21 5G 128GB - Grey - 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
13/04/2026
Dawn W.
Verified purchase
Reviewed 06/06/2025, United Kingdom.
Fabulous phone, arrived very quickly, chose a refurbished s21 and the condition is amazing I love it I've used back market before and I'll be using it in the future as well as recommending it to everyone I know 👌
Galaxy S21 5G 128GB - Grey - Unlocked
Galaxy S21 5G 128GB - Grey - 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
22/05/2025
Jane A.
Verified purchase
Reviewed 15/11/2024, United Kingdom.
Thankyou BackMarket you made my purchase thr best decision i have made when it come to choosing my phone. The phone arrived quickly even though it was a refurbished one it looked brand new, the phone was i pristine condition and works perfictly, I would definatly recommend to anyone.
Galaxy S21 5G 128GB - Grey - Unlocked
Galaxy S21 5G 128GB - Grey - Unlocked
Condition
Premium
Close to perfection. The body may have tiny micro-scratches. For items with screens, the screen will be flawless.
Purchased
13/09/2024

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

Durability
Overall performance
Camera
Screen quality

0.46SAR head
10 megapixelsFront camera
SM-G991BManufacturer Ref
USB-CConnector
Physical SIM + eSIMSIM card
6.2Screen size (in)
Dynamic AMOLED 2XScreen type
GreyColour
NoSD Card Slot

The Galaxy S21 5G is a flagship smartphone from Samsung, released in January 2021. This model features a sleek design and advanced capabilities, making it suitable for users who appreciate both style and performance.

Key features:

Display: 6.2-inch Dynamic AMOLED 2X, FHD+ resolution
Processor: Exynos 2100 (or Snapdragon 888, depending on the region)
Camera: Triple rear cameras with a 12MP ultra-wide, 12MP wide, and 64MP telephoto lens
Connectivity: 5G compatible for fast data speeds
Operating System: Ships with Android 11, upgradable to the latest versions

Who is this for?

The Galaxy S21 5G is ideal for professionals, content creators, and everyday users looking for a powerful smartphone with a versatile camera system. It suits those who enjoy streaming, gaming, and photography, providing a balanced experience compared to newer models like the Galaxy S22.

Pros & Cons:

Pros	Cons
High-quality display with vibrant colours and deep blacks.	No expandable storage option.
Solid camera performance in various lighting conditions.	Battery life may not last as long as newer models.

Why refurbished?

Choosing a refurbished Galaxy S21 5G allows you to access premium features while being environmentally conscious. Each device is rigorously tested to ensure quality and reliability. Learn more about our quality standards.

SAR head: 0.46
Front camera: 10 megapixels
Manufacturer Ref: SM-G991B
Connector: USB-C
SIM card: Physical SIM + eSIM
Screen size (in): 6.2
Screen type: Dynamic AMOLED 2X
Colour: Grey
SD Card Slot: No
Colour (official name): Phantom Gray
Compatible with latest Update: Yes
Year of Release: 2021
Resolution: 1080 x 2400
Weight: 171 g
Main camera: 12 megapixels
Model: Galaxy S21 5G
Serie: Samsung Galaxy S
SAR body: 1.51
Brand: Samsung
Mobile network: 5G
Carrier compatibility: Unlocked
Foldable: No
Memory (GB): 8 GB
OS: Android
Camera Type: Triple (3x)
Storage: 128 GB

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Galaxy S21 5GGrey • 128 GB • Physical SIM + eSIM

Galaxy S21 5GGrey • 128 GB • Physical SIM + eSIM

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Customer reviews for Galaxy S21 5G

Overall rating

Rating details

Reviews

Reviews

Al B.

Kane G.

Denise R.

Jenny B.

Matthew S.

Dawn W.

Jane A.

Popular searches

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

Durability

Overall performance

Camera

Screen quality

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