Samsung Galaxy S21 vs Samsung Galaxy S25+
Our Verdict: The Galaxy S21 and the Galaxy S25+ are four years apart, which is enough for a real difference. The S21 5G leads on camera hardware with a 64MP main sensor to the S25+'s 50MP, and the S25+ has the bigger battery of the two, 4900mAh against 4000mAh, which should mean longer between charges in day-to-day use. The S25+ has the stronger screen, bigger at 6.7" against 6.2" and sharper at 513 PPI, and the S25+ offers up to 512GB of storage versus 256GB on the S21 5G. The S25+ is the better phone; upgrade from the S21 5G if you want the newer hardware, or hold on if yours still does the job.
Buying outright, the S21 5G starts at £145 SIM-free.
10 reviews 4.0
10 reviews
Prices updated 27 July 2026
Samsung Galaxy S21
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Samsung Galaxy S25+
|
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|---|---|---|
| Expert Rating | 4.1 10 reviews |
4.0 10 reviews |
| Screen | 6.2" | 6.7" |
| Display | Dynamic AMOLED 2X | Dynamic LTPO AMOLED 2X |
| Resolution | 1080 x 2400 | 1440 x 3120 |
| Pixels Per Inch | 424 | 513 |
| Rear Camera | 64 Megapixels | 50 Megapixels |
| Front Camera | 10 Megapixels | 12 Megapixels |
| Chipset | Exynos 2100 | Qualcomm SM8750-AB Snapdragon 8 Elite (3 nm) |
| Battery | 4,000 mAh | 4,900 mAh |
| Storage | 128GB, 256GB | 256GB, 512GB |
| OS | Android 11 | Android 15 |
| SIM Type | Nano SIM | nano-SIM and e-SIM |
| Connectivity | Up to 5G | Up to 5G |
| Wi-Fi | 802.11 a/b/g/n/ac/6 | 802.11 a/b/g/n/ac/6e |
| Bluetooth | 5.0 with A2DP, LE | 5.4, A2DP, LE |
| Dimensions | 151.7 x 71.2 x 7.9 mm | 158.44 x 75.79 x 7.35 mm |
| Weight | 171 grams | 190 grams |
| Water Resistance | IP53 - dust and splash protection | IP68 - Dust and water resistant over 1.5 meter and 30 minutes |
| Contracts | - |
£69.83/mo
£30.00 upfront |
| SIM-free | £144.99 | £539.99 |
| Prices updated 27 July 2026 | ||
| Deals | Deals | |
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Frequently Asked Questions
Which has the better screen, the Samsung Galaxy S21 or Samsung Galaxy S25+?
The Samsung Galaxy S25+ has the bigger screen at 6.7" compared to the Samsung Galaxy S21's 6.2", the Samsung Galaxy S25+ has the sharper display at 513 pixels per inch versus 424, and the Samsung Galaxy S21 uses a Dynamic AMOLED 2X panel while the Samsung Galaxy S25+ has a Dynamic LTPO AMOLED 2X.
Which has the better camera, the Samsung Galaxy S21 or Samsung Galaxy S25+?
The Samsung Galaxy S21 features a 64 Megapixels rear camera, while the Samsung Galaxy S25+ has a 50 Megapixels rear camera. Both devices also have front-facing cameras for selfies and video calls.
Which is cheaper to buy SIM-free, the Samsung Galaxy S21 or Samsung Galaxy S25+?
The Samsung Galaxy S21 is cheaper SIM-free, starting from £144.99.
What storage options are available for the Samsung Galaxy S21 and Samsung Galaxy S25+?
The Samsung Galaxy S21 is available in 128GB, 256GB, while the Samsung Galaxy S25+ comes in 256GB, 512GB.
What processors do the Samsung Galaxy S21 and Samsung Galaxy S25+ use?
The Samsung Galaxy S21 is powered by the Exynos 2100, while the Samsung Galaxy S25+ uses the Qualcomm SM8750-AB Snapdragon 8 Elite (3 nm).
Which is easier to carry and hold, the Samsung Galaxy S21 or Samsung Galaxy S25+?
The Samsung Galaxy S21 is the more portable of the two: it's 19g lighter at 171 grams, it's also the more compact phone at 151.7 x 71.2 x 7.9 mm, the Samsung Galaxy S25+ is slimmer at 7.35mm thick.
Which is more water resistant, the Samsung Galaxy S21 or Samsung Galaxy S25+?
The Samsung Galaxy S21 is rated IP53 - dust and splash protection, while the Samsung Galaxy S25+ is rated IP68 - Dust and water resistant over 1.5 meter and 30 minutes.
What operating system do the Samsung Galaxy S21 and Samsung Galaxy S25+ run?
The Samsung Galaxy S21 runs Android 11 and the Samsung Galaxy S25+ runs Android 15. This is one of the biggest factors when choosing between the two, as each ecosystem has its own apps, services and features.