Samsung Galaxy S21 vs Samsung Galaxy S25 FE
Our Verdict: There's four years between the Galaxy S21 and the Galaxy S25 FE, so the Galaxy S25 FE is ahead on most things. The S21 5G has a noticeably higher-resolution main camera, 64MP against the S25 FE's 50MP, and the S25 FE packs the bigger battery, 4900mAh against 4000mAh, which usually means longer between charges. The S25 FE has the bigger screen at 6.7" against 6.2", while the S21 5G has the sharper one at 424 PPI, and storage goes higher on the S25 FE, up to 512GB against 256GB. Coming from the S21 5G, the S25 FE is a genuine upgrade rather than a token one.
If you'd rather pay up front, the S21 5G is the cheaper buy at £150 SIM-free.
10 reviews 4.0
10 reviews
Prices updated 27 July 2026
Samsung Galaxy S21
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Samsung Galaxy S25 FE
|
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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 | 1080 x 2340 |
| Pixels Per Inch | 424 | 385 |
| Rear Camera | 64 Megapixels | 50 Megapixels |
| Front Camera | 10 Megapixels | 12 Megapixels |
| Chipset | Exynos 2100 | Exynos 2400 (4 nm) |
| Battery | 4,000 mAh | 4,900 mAh |
| Storage | 128GB, 256GB | 128GB, 256GB, 512GB |
| OS | Android 11 | Android 16 |
| 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 | 161.3 x 76.6 x 7.4 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 | - |
£23.54/mo
£9.00 upfront |
| SIM-free | £149.99 | £399.99 |
| 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 FE?
The Samsung Galaxy S25 FE has the bigger screen at 6.7" compared to the Samsung Galaxy S21's 6.2", the Samsung Galaxy S21 has the sharper display at 424 pixels per inch versus 385, and the Samsung Galaxy S21 uses a Dynamic AMOLED 2X panel while the Samsung Galaxy S25 FE has a Dynamic LTPO AMOLED 2X.
Which has the better camera, the Samsung Galaxy S21 or Samsung Galaxy S25 FE?
The Samsung Galaxy S21 features a 64 Megapixels rear camera, while the Samsung Galaxy S25 FE 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 FE?
The Samsung Galaxy S21 is cheaper SIM-free, starting from £149.99.
What storage options are available for the Samsung Galaxy S21 and Samsung Galaxy S25 FE?
The Samsung Galaxy S21 is available in 128GB, 256GB, while the Samsung Galaxy S25 FE comes in 128GB, 256GB, 512GB.
What processors do the Samsung Galaxy S21 and Samsung Galaxy S25 FE use?
The Samsung Galaxy S21 is powered by the Exynos 2100, while the Samsung Galaxy S25 FE uses the Exynos 2400 (4 nm).
Which is easier to carry and hold, the Samsung Galaxy S21 or Samsung Galaxy S25 FE?
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 FE is slimmer at 7.4mm thick.
Which is more water resistant, the Samsung Galaxy S21 or Samsung Galaxy S25 FE?
The Samsung Galaxy S21 is rated IP53 - dust and splash protection, while the Samsung Galaxy S25 FE 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 FE run?
The Samsung Galaxy S21 runs Android 11 and the Samsung Galaxy S25 FE runs Android 16. This is one of the biggest factors when choosing between the two, as each ecosystem has its own apps, services and features.