Samsung Galaxy S21 Ultra vs Samsung Galaxy S25+
Our Verdict: The Galaxy S25+ is four years newer than the Galaxy S21 Ultra, and it shows in the specs. The S21 Ultra 5G has the better camera on paper, 108MP versus 50MP, plus a 40MP selfie camera against 12MP, and the S25+ is the lighter phone at 190g against 228g. If you're on the S21 Ultra 5G, the S25+ is a real step up, but only worth it if the changes above matter to you.
Buying outright, the S21 Ultra 5G starts at £210 SIM-free.
10 reviews 4.0
10 reviews
Prices updated 25 July 2026
Samsung Galaxy S21 Ultra
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Samsung Galaxy S25+
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|---|---|---|
| Expert Rating | 4.4 10 reviews |
4.0 10 reviews |
| Screen | 6.8" | 6.7" |
| Display | Dynamic AMOLED 2X capacitive touchscreen | Dynamic LTPO AMOLED 2X |
| Resolution | 1440 x 3200 | 1440 x 3120 |
| Pixels Per Inch | 516 | 513 |
| Rear Camera | 108 Megapixels | 50 Megapixels |
| Front Camera | 40 Megapixels | 12 Megapixels |
| Chipset | Exynos 2100 | Qualcomm SM8750-AB Snapdragon 8 Elite (3 nm) |
| Battery | 5,000 mAh | 4,900 mAh |
| Storage | 128GB, 256GB, 512GB | 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 | 5.1 with A2DP, LE | 5.4, A2DP, LE |
| Dimensions | 165.1 x 75.6 x 8.9 mm | 158.44 x 75.79 x 7.35 mm |
| Weight | 228 grams | 190 grams |
| Water Resistance | IP68 - Dust and water resistant over 1.5 meter and 30 minutes | IP68 - Dust and water resistant over 1.5 meter and 30 minutes |
| Contracts | - |
£69.83/mo
£30.00 upfront |
| SIM-free | £209.99 | £539.99 |
| Prices updated 25 July 2026 | ||
| Deals | Deals | |
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Frequently Asked Questions
Which has the better screen, the Samsung Galaxy S21 Ultra or Samsung Galaxy S25+?
Both phones have a similar screen size at around 6.8", both screens are similarly sharp at around 516 pixels per inch, and the Samsung Galaxy S21 Ultra uses a Dynamic AMOLED 2X capacitive touchscreen panel while the Samsung Galaxy S25+ has a Dynamic LTPO AMOLED 2X.
Which has the better camera, the Samsung Galaxy S21 Ultra or Samsung Galaxy S25+?
The Samsung Galaxy S21 Ultra features a 108 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 Ultra or Samsung Galaxy S25+?
The Samsung Galaxy S21 Ultra is cheaper SIM-free, starting from £209.99.
What storage options are available for the Samsung Galaxy S21 Ultra and Samsung Galaxy S25+?
The Samsung Galaxy S21 Ultra is available in 128GB, 256GB, 512GB, while the Samsung Galaxy S25+ comes in 256GB, 512GB.
What processors do the Samsung Galaxy S21 Ultra and Samsung Galaxy S25+ use?
The Samsung Galaxy S21 Ultra 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 Ultra or Samsung Galaxy S25+?
The Samsung Galaxy S25+ is the more portable of the two: it's 38g lighter at 190 grams, it's also the more compact phone at 158.44 x 75.79 x 7.35 mm, and is slimmer at 7.35mm thick.
Which is more water resistant, the Samsung Galaxy S21 Ultra or Samsung Galaxy S25+?
Both phones share the same water resistance rating of IP68 - Dust and water resistant over 1.5 meter and 30 minutes.
What operating system do the Samsung Galaxy S21 Ultra and Samsung Galaxy S25+ run?
The Samsung Galaxy S21 Ultra 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.