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

(18,954 reviews)

£122.00

before trade-in

Save £737.00

Free delivery by 10 - 11 Jun

Restored professionally

Based on up to 100-points of inspection

Customer reviews for Galaxy S21 5G

Overall rating

18,954 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
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
Colette A.
Verified purchase
Reviewed 25/05/2026, United Kingdom.
Fantastic. Delivered quicker than date advised and although the product was said to be in fair condition, I would describe it as excellent! Have used back market a couple of times now and have advised others to do the same.
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
11/05/2026
Elaine T.
Verified purchase
Reviewed 15/03/2026, United Kingdom.
Perfect as usual this is the 3rd phone I've bought from backmarket.co.uk S25 ultra for myself, S22 for older granson and the S21 for younger granson and they have all came in amazing condition and work perfectly. I will never again get a phone on contract after learning about backmarket. 🥰👌🥰
Galaxy S21 5G 256GB - Grey - Unlocked
Galaxy S21 5G 256GB - 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
28/02/2026
Edward P.
Verified purchase
Reviewed 21/07/2025, United Kingdom.
I have used black market for my wife's and my last three phones. every time the phones have been in perfect condition and worked with no problems at all. I have just bought a duel sim phone Galaxy S21 5G because I used one sim for Internet at my caravan and normal sim for phone. works perfect for me.
Galaxy S21 5G 128GB - White - Unlocked
Galaxy S21 5G 128GB - White - 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
05/07/2025
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

15,17 cmHeight
0,456SAR head
NoSD Card Slot
SamsungBrand
12 megapixelsMain camera
10 megapixelsFront camera
1,509SAR body
8 GBMemory (GB)
5GMobile network

The Galaxy S21 5G is a powerful smartphone that combines cutting-edge technology with a sleek design. Released in January 2021, this device remains a strong contender in the smartphone market, offering 5G connectivity and impressive camera capabilities.

Key features:

Release Date: January 2021
Display: 6.2-inch Dynamic AMOLED 2X, FHD+ resolution
Processor: Exynos 2100 (International) / Snapdragon 888 (USA)
Camera: Triple-camera system with 12MP ultra-wide, 12MP wide, and 64MP telephoto lenses
Connectivity: 5G compatible for ultra-fast downloads and low-latency performance.

Who is this for?

The Galaxy S21 5G is ideal for users looking for a high-performance smartphone with excellent camera features. It suits students, professionals, and anyone who enjoys capturing high-quality photos and videos while staying connected with the latest technology.

Pros & Cons:

Pros	Cons
Vibrant display with 120Hz refresh rate.	No expandable storage option.
Versatile camera system for various photography styles.	Plastic back may feel less premium than glass alternatives.

Why refurbished?

Choosing a refurbished Galaxy S21 5G allows you to enjoy a top-tier smartphone while being eco-conscious. Each device is thoroughly inspected and tested to meet Back Market’s quality standards, ensuring reliability. Learn more about our quality standards.

Height: 15,17 cm
SAR head: 0,456
SD Card Slot: No
Brand: Samsung
Main camera: 12 megapixels
Front camera: 10 megapixels
SAR body: 1,509
Memory (GB): 8 GB
Mobile network: 5G
Camera Type: Triple (3x)
Colour (official name): Phantom gray
Carrier compatibility: Unlocked
Weight: 169 g
Width: 7,12 cm
Depth: 0,79 cm
Colour: Grey
Serie: Samsung Galaxy S
OS: Android
Storage: 128 GB
Connector: USB-C
Manufacturer Ref: SM-G991B/DS
Model: Galaxy S21 5G
SIM card: Dual Physical SIM + eSIM
Resolution: 1080 x 2400
Year of Release: 2021
Compatible with latest Update: Yes
Screen type: Dynamic AMOLED 2X
Foldable: No
Screen size (in): 6.2

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

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

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Customer reviews for Galaxy S21 5G

Overall rating

Rating details

Reviews

Reviews

Al B.

Matthew S.

Colette A.

Elaine T.

Edward P.

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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