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

(19,294 reviews)

£136.00

before trade-in

Save £723.00

Free delivery by 14 - 15 Sept

Express delivery by 11-14 Sept from £5.00

Restored professionally

Based on up to 100-points of inspection

Customer reviews for Galaxy S21 5G

Overall rating

19,294 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
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
Amy W.
Verified purchase
Reviewed 11/11/2024, United Kingdom.
I've used Back market for tech over the last 2-3 years now and have always found it to be great. Good choice of products, wide variety of condition and price, something for every budget. Quick service, reliable, even when there's a problem its dealt with quickly and efficiently. I have been highly recommending you to all my and friends. Buying reconditioned products is good for the environment and that's really important to me. 5 star products with great customer service and good for the planet.
Galaxy S21 5G 128GB - Purple - Unlocked
Galaxy S21 5G 128GB - Purple - Unlocked
Condition
Premium
Close to perfection. The body may have tiny micro-scratches. For items with screens, the screen will be flawless.
Purchased
12/09/2024

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

Durability
Overall performance
Camera
Screen quality

0,79 cmDepth
1080 x 2400Resolution
7,12 cmWidth
Samsung Galaxy SSerie
SamsungBrand
12 megapixelsMain camera
10 megapixelsFront camera
NoFoldable
Phantom grayColour (official name)

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.

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

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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.

Kane G.

Denise R.

Matthew S.

Dawn W.

Jane A.

Amy W.

Popular searches

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

Durability

Overall performance

Camera

Screen quality

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