Galaxy S21 Ultra 5G128 GB•Black

4.7/5(674 reviews)

£316.25

Save £999.75

Standard Delivery by 14 - 16 OctExpress Delivery by 12 Oct for £12.00

Restored professionally

Based on up to 100-points of inspection

The PhoneMart Promise

Based on up to 100-points of inspection

We measure each battery's health and capacity against strict standards, and replace any that don't make the grade, so you get power you can rely on all day.
The display is switched on and looked over closely for any blemishes, so there are no marks, dust spots or discolouration to spoil the view.
Where a charger is included, the cord and connectors are checked for wear, and the plug is confirmed to fit sockets.
Before it ships, every device gets a thorough professional clean and polish so it feels fresh in your hands.
Every lens is put to work, so we can confirm sharp photos, smooth video and reliable performance on video calls.
A full factory reset wipes the device clean, securely erasing all previous data and restoring the original settings.
We confirm the network status up front, so you know exactly whether the device is locked or unlocked before it arrives.
Cards are inserted to make sure the device reads SIM and memory cards correctly, and that every tray and slot works smoothly.
Each button is pressed to check it responds straight away and does exactly what it should, from volume to lock to power.
If any parts are fitted during refurbishment, they are tested for compatibility and held to the same standards as the originals.
We run the IMEI to confirm it is clean and never blacklisted, and that the device details match the manufacturer's records.
The moisture indicator inside the device is inspected to rule out any history of water or liquid damage.
Every port, including the headphone, USB and Ethernet connections, is checked to make sure it connects and works reliably.
Face and fingerprint unlock, along with any voice recognition, are tested to make sure they work quickly and accurately.
Positioning is checked for accurate GPS, so maps and location apps behave exactly as they should.
External sensors, such as proximity, brightness, laser measurement and heart rate, are checked for precise and responsive readings.
Screws, casing, frames and other mechanical parts are examined to confirm they are original or quality replacements, and any replacement has to match or beat industry standards.
We confirm that Wi-Fi and Bluetooth connect quickly and hold a stable signal.
Speakers and microphones are inspected and fine tuned so audio records and plays back clearly.
The flash and every indicator light are tested to confirm they light up and work correctly.
Any features that are specific to your device are checked against the same standards, so nothing gets missed.

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Body

Almost no signs of useVerified partsBattery for daily use

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Galaxy S21 Ultra 5G

Excellent
Standard battery
Black
128 GB
Dual Physical SIM + eSIM

£316.25

£1,316.00 newSave £999.75

14-day returns

Set up the return in just a few clicks in your PhoneMart account.

Send the device back within 14 days of receiving it. Return postage is paid by you unless the item is faulty, damaged or not what you ordered.

Get your cash back within 3 business days of the seller receiving the device.

Proudly refurbished by PhoneMart Privacy policy

Comes with

Compatible charging cable

Excellent-Standard battery-Black-128 GB-Dual Physical SIM + eSIM

£316.25

£1,316.00 newSave £999.75

£316.25

£1,316.00 newSave £999.75

Customer reviews for Galaxy S21 Ultra 5G

Overall rating

4.7/5

674 verified reviews

Rating details

Appearance: 4.7/5
Battery: 4.4/5
Delivery: 4.8/5

Top reviews with photos

Reviews

Lindsey Hardy

Verified purchase

5/5

Reviewed 24/06/2026, United Kingdom.

The phone arrived in perfect condition, exactly what I wanted.

Galaxy S21 Ultra 5G 256GB Silver Unlocked | PhoneMartSee item

Condition GoodPurchased 10/06/2026

Chris Pollard

Verified purchase

5/5

Reviewed 09/03/2025, United Kingdom.

Good prices and the phone was in great condition even though I didn't pick the highest quality option.

Galaxy S21 Ultra 5G 256GB Dark Blue Unlocked | PhoneMartSee item

Condition FairPurchased 21/02/2025

Simon Greenwood

Verified purchase

5/5

Reviewed 03/01/2025, United Kingdom.

Good phone, good price.

Galaxy S21 Ultra 5G 128GB Black Unlocked | PhoneMartSee item

Condition FairPurchased 14/12/2024

Chris Slater

Verified purchase

5/5

Reviewed 28/11/2024, United Kingdom.

This is my second purchase from PhoneMart. My S10+ arrived in excellent condition and has worked perfectly for over two years. Now my S21 Ultra has arrived in excellent condition too. Both were well packaged and came quickly. This company is brilliant and I have no hesitation recommending it. Thanks all.

Galaxy S21 Ultra 5G 128GB Black Unlocked | PhoneMartSee item

Condition ExcellentPurchased 12/11/2024

Roger Hopkins

Verified purchase

5/5

Reviewed 11/01/2024, United Kingdom.

This is my second purchase from PhoneMart (this one was for my wife). Delivery was very quick, two days. The quality is great with no marks at all, even though it was marked as good condition. Charged it, transferred the data, and it works perfectly. Good buy.

Galaxy S21 Ultra 5G 128GB Black Unlocked | PhoneMartSee item

Condition FairPurchased 29/12/2023

Kim Cooper

Verified purchase

5/5

Reviewed 01/09/2026, United Kingdom.

I checked the phone when it arrived and it looks perfect. I have not used it yet since it is a Christmas present.

Galaxy S21 Ultra 5G 128GB Black Unlocked | PhoneMartSee item

Condition ExcellentPurchased 23/08/2026

Ruth Bryant

Verified purchase

5/5

Reviewed 29/08/2026, United Kingdom.

Galaxy S21 Ultra 5G 256GB Silver Unlocked | PhoneMartSee item

Condition FairPurchased 18/08/2026

David Gordon

Verified purchase

5/5

Reviewed 27/08/2026, United Kingdom.

The phone itself was very good. The trade-in deal felt like a total scam.

Galaxy S21 Ultra 5G 128GB Black Unlocked | PhoneMartSee item

Condition FairPurchased 15/08/2026

Blacklab Mills

Verified purchase

5/5

Reviewed 27/08/2026, United Kingdom.

I ordered a premium grade phone. It looks and feels like new. It arrived on time with plenty of tracking information. I am quite pleased so far. This is my first time buying a refurbished device.

Galaxy S21 Ultra 5G 128GB Black Unlocked | PhoneMartSee item

Condition FairPurchased 19/08/2026

Todd Owen

Verified purchase

5/5

Reviewed 18/08/2026, United Kingdom.

spot on very pleased

Galaxy S21 Ultra 5G 256GB Dark grey Unlocked | PhoneMartSee item

Condition GoodPurchased 04/08/2026

Common questions about the Galaxy S21 Ultra 5G

Durability

Overall performance

Camera

Screen quality

Black

Colour

128 GB

Storage

Dual Physical SIM + eSIM

Sim

Quadruple (4x)

Camera type

Unlocked

Carrier compatibility

Yes

Compatible with latest update

USB-C

Connector

Foldable

40 megapixels

Front camera

For those who want a phone that handles demanding apps and delivers sharp, detailed photos, the Galaxy S21 Ultra 5G is built to perform. Its 12 GB of memory keeps multitasking smooth, while the 6.8-inch Dynamic AMOLED 2X screen brings videos and games to life with rich colours and sharp resolution.

The Galaxy S21 Ultra 5G, released in 2021, suits anyone needing a powerful unlocked Android phone that keeps pace with 5G networks. The quadruple camera system, led by a 108-megapixel main lens and a 40-megapixel front camera, lets you capture detailed shots from everyday moments to special events.

Key features

Screen Size: 6.8 inches Dynamic AMOLED 2X for vivid visuals
Memory: 12 GB RAM, smooth multitasking
Camera: Quadruple setup with 108MP main lens
Mobile Network: 5G for fast internet access
Carrier: Unlocked, works with any network
Sim Card: Physical SIM plus eSIM support

Who is this for?

The Galaxy S21 Ultra 5G fits users who want top-tier camera quality for photography and video, whether for social sharing or creative projects. It also works well for people who rely on a large, vibrant display for watching content or gaming on the go.

It's a good match for professionals who need a powerful Android phone unlocked for any carrier, supporting both physical SIM and eSIM for flexible connectivity. If you want a phone that handles daily multitasking with ease and runs the latest Android updates, this is a solid choice.

What you get and what to know

What you get	Good to know
Quadruple camera system for detailed photos and video	Physical SIM + eSIM supports dual SIM use
12 GB RAM handles multitasking smoothly	No SD card slot internal storage only
Unlocked carrier use with any network	Weight 227 g solid, substantial feel

Why buy it refurbished?

Choosing a refurbished Galaxy S21 Ultra 5G means you get a thoroughly inspected phone. Each device passes up to a 100-point quality check covering all major functions from screen to cameras and connectivity, ensuring full working order.

Buying refurbished also reduces electronic waste by keeping devices in use longer and lowers the demand for new materials. Every order comes with free delivery, a 24-month warranty, and 14-day returns, making your purchase secure and responsible.

ColourBlack

Storage128 GB

SimDual Physical SIM + eSIM

Camera typeQuadruple (4x)

Carrier compatibilityUnlocked

Compatible with latest updateYes

ConnectorUSB-C

FoldableNo

Front camera40 megapixels

Main camera108 megapixels

Memory gb12 GB GB

Mobile network5G

OsAndroid

Resolution1440 x 3200

Sar body1.58

Sar head0.71

Screen size in6.8 inch

Screen typeDynamic AMOLED 2X

Sd card slotNo

Sim cardPhysical SIM + eSIM

Weight227 g g

Year of release2021

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Galaxy S21 Ultra 5G128 GB•Black

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Customer reviews for Galaxy S21 Ultra 5G

Overall rating

Rating details

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Reviews

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Common questions about the Galaxy S21 Ultra 5G

Key features

Who is this for?

What you get and what to know

Why buy it refurbished?

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