Galaxy S21 5G • UnlockedBlack • 128 GB • Physical SIM + eSIM

(2,805 reviews)

$158.00

Save $301.00

Free delivery by Jun 8 - 9

Express delivery by Jun 5 - 8 from $15.00

Restored professionally

Based on up to 100 points of inspection

Customer reviews for Galaxy S21 5G • Unlocked

Overall rating

2,805 verified reviews

Rating details

Accessories
4.1/5
Appearance
4.2/5
Battery
4.1/5
Lens & Camera
4.4/5
Overall performance
4.2/5
Packaging
4.4/5
Shipping
4.5/5

Reviews

Harry M.
Verified purchase
Reviewed 2/15/26, United States.
Great product! Looks and acts like it is new. Specifically being used to extend medical device signals to my personall Cell Phone. Very pleased with the quality and expediant delivery. It's my second device from Back Market and both have been great!
Galaxy S21 5G 128GB - Gray - Unlocked
Galaxy S21 5G 128GB - Gray - Unlocked
Condition
Fair
Signs of wear. The body may have a few visible scratches and dents. Items with screens may have light scratches.
Purchased
2/2/26
Heriberto D.
Verified purchase
Reviewed 1/22/25, United States.
I got it a day earlier ! And it was a little scratched from the top but it’s so worthy buying especially since I got it in a (fair) condition the screen and everything else was ok and worked perfectly fine really recommend and will be buying again thank you !!!
Galaxy S21 5G 128GB - Gray - Unlocked
Galaxy S21 5G 128GB - Gray - Unlocked
Condition
Fair
Signs of wear. The body may have a few visible scratches and dents. Items with screens may have light scratches.
Purchased
1/18/25
Valorie C.
Verified purchase
Reviewed 11/25/25, United States.
I ordered my Galaxy S21 5G from Backmarket after a recommendation from a rep at a local battery shop. My other Samsung was having numerous issues but a brand new phone was not an option. Luckily, I had jotted down the info and looked up Backmarket that same night and was impressed with the reviews. It was easy to order and arrived as promised. It sat on my side table for a couple of weeks as I was unsure if I could do the set up myself. Thank goodness for You Tube! Tech savvy I am not. But I do know how to follow directions and save for a couple of little hiccups, I was up and running in an hour. So far, so good and I would recommend Backmarket to anyone looking to upgrade for a lot less.
Galaxy S21 5G 128GB - Gray - Unlocked
Galaxy S21 5G 128GB - Gray - Unlocked
Condition
Fair
Signs of wear. The body may have a few visible scratches and dents. Items with screens may have light scratches.
Purchased
11/12/25
Theresa M.
Verified purchase
Reviewed 11/24/25, United States.
Arrived quickly and well packaged. I appreciate that you guys have a page to help with transferring info from old devices to new ones, so it was super easy to switch my phone over. I'm so happy I found this company - I prefer buying refurbished and used things, especially when they work perfectly fine. Very affordable too.
Galaxy S21 5G 256GB - Gray - Unlocked
Galaxy S21 5G 256GB - Gray - Unlocked
Condition
Good
Light signs of wear. The body may have light micro-scratches. For items with screens, the screen will have no scratches.
Purchased
11/13/25
Jakson B.
Verified purchase
Reviewed 11/19/24, United States.
I recently purchased a refurbished Samsung Galaxy S21 from BackMarket, and I couldn't be happier with my experience. Here's a breakdown of my thoughts The phone arrived in excellent condition, just as described on the website. I opted for the "Excellent" grade, and true to its word, the device looked almost brand-new. There were no noticeable scratches or signs of wear, and the performance has been flawless so far. Pricing The pricing was very competitive compared to buying new or from other retailers. I saved a significant amount without sacrificing quality, which made it feel like a great deal. Shipping and Packaging The shipping was fast and efficient. The phone was securely packaged, ensuring it arrived in perfect condition. I appreciated the eco-friendly packaging, which aligns with BackMarket's commitment to sustainability. Performance The Samsung S21 is a fantastic phone with a vibrant display, excellent camera quality, and speedy performance. Thanks to BackMarket's thorough refurbishing process, the device operates like new. Overall Experience BackMarket provided a seamless buying experience. From the user-friendly website to the quality of the product, everything exceeded my expectations. If you're looking to save money while supporting sustainability, I highly recommend checking out BackMarket. Rating: 5/5
Galaxy S21 5G 128GB - Purple - Unlocked
Galaxy S21 5G 128GB - Purple - Unlocked
Condition
Good
Light signs of wear. The body may have light micro-scratches. For items with screens, the screen will have no scratches.
Purchased
11/16/24
Kody S.
Verified purchase
Reviewed 3/12/26, United States.
I am pleased to say that she was able to activate and use her phone she loves it. I am glad that I received it and had no issues compared to the new phone I bought on Amazon store front and it was locked and had to send back get money back. So thank you for making my wife happy. Happy wife happy life.
Galaxy S21 5G 128GB - Gray - Unlocked
Galaxy S21 5G 128GB - Gray - 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
2/13/26
Franchesca I.
Verified purchase
Reviewed 4/6/25, United States.
This is the 3rd time I've purchased a refurbished phone from backmarket. I am absolutely a loyal customer and fan now so much so that I have recommended this site to everyone I know who's in the market for a new phone tablet ect. I love my s25 and have had no problems and the trade in program rocks! I love it!
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
3/24/25

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

Durability
Overall performance
Camera
Screen quality

5 ozWeight
6.2Screen size (inches)
8 GBMemory (GB)
NoFoldable
0.74SAR head
2021Release Year
Dynamic AMOLED 2XScreen type
1080 x 2400Resolution
SM-G991WManufacturer Ref.

The Galaxy S21 5G is a flagship smartphone from Samsung, introduced in early 2021. It offers a balance of performance, design, and connectivity, making it suitable for users who want a reliable device for everyday use.

Key features:

Display: 6.2-inch Dynamic AMOLED 2X, FHD+ resolution
Processor: Exynos 2100 (Global) or Snapdragon 888 (USA)
Camera: Triple rear cameras with 12MP wide, 64MP telephoto, and 12MP ultra-wide lenses
Operating System: Ships with Android 11, upgradable to newer versions
Connectivity: 5G capable for fast network performance

Who is this for?

The Galaxy S21 5G is ideal for tech enthusiasts, professionals, or anyone seeking a high-performance smartphone with a vibrant display and advanced camera system. It’s well-suited for users who want a premium device without the latest model’s cost.

Pros & Cons: Pros Cons Excellent AMOLED display with high refresh rate. No expandable storage slot. Powerful Snapdragon 888 or Exynos 2100 chip for smooth multitasking. Battery life varies depending on usage, but not included in specifications.
Why refurbished?

Choosing a refurbished Galaxy S21 5G allows you to access a high-quality device at a more affordable price point. Each device is tested and certified to meet Back Market’s quality standards, ensuring reliability and good condition. Learn more about our quality standards.

Weight: 5 oz
Screen size (inches): 6.2
Memory (GB): 8 GB
Foldable: No
SAR head: 0.74
Release Year: 2021
Screen type: Dynamic AMOLED 2X
Resolution: 1080 x 2400
Manufacturer Ref.: SM-G991W
Serie: Samsung Galaxy S
SIM card: Physical SIM + eSIM
Last OS Compatibility: Yes
Front camera: 10 megapixels
Brand: Samsung
Main camera: 12 megapixels
Carrier compatibility: Unlocked
Color: Black
Color (official name): Black
Network: 5G
Model: Galaxy S21 5G
OS: Android
Storage: 128 GB
Memory Card Slot: No

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Galaxy S21 5G • UnlockedBlack • 128 GB • Physical SIM + eSIM

Galaxy S21 5G • UnlockedBlack • 128 GB • Physical SIM + eSIM

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Customer reviews for Galaxy S21 5G • Unlocked

Overall rating

Rating details

Reviews

Reviews

Harry M.

Heriberto D.

Valorie C.

Theresa M.

Jakson B.

Kody S.

Franchesca I.

Popular searches

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

Durability

Overall performance

Camera

Screen quality

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