Should I upgrade my Galaxy S21?
The Samsung Galaxy S21 went on sale on 29 January 2021, launched at £769 (Samsung Newsroom UK — Galaxy S21 5G and S21+ 5G). It has a 6.2-inch display, a weight of 169 g, the Exynos 2100, 5nm chip, a 12 MP main camera and 128 GB of storage to start. Samsung claims up to 20 hours of video playback. Security updates are committed until 21 February 2026. Every figure in the Samsung Galaxy S21 specifications below links the page it came from and the date it was read.
5.7 years oldPatches ended 2026-02-21Read
Is it still supported?
No. The maker’s security-update window for the Galaxy S21 closed on 2026-02-21. That is the one reason to move that does not depend on any figure below.endoflife.date — Samsung mobile, retrieved 2026-09-06
What the Galaxy S26 changes
The newest Samsung phone in this line is the Galaxy S26 at £879, released 6 March 2026. Judged row by row against our published thresholds; the full table is at Galaxy S26 vs Galaxy S21.
On the makers’ figures and the named third-party sources, the Galaxy S26 wins on peak brightness (2,600 nits against 1,300 nits, both from GSMArena), storage (base) (256 GB against 128 GB) and claimed video playback (30 h against 20 h). One gap is borderline, a difference most people would not notice: RAM (12 GB against 8 GB) for the Galaxy S26. The differences in weight, display size and battery capacity are below the thresholds you would notice. Both state the same refresh rate, fast charging and wireless charging. The other 37 rows have no threshold or no direction to judge by, so nobody wins them.
- Peak brightness: 1,300 nits → 2,600 nits
- Storage (base): 128 GB → 256 GB
- Claimed video playback: 20 h → 30 h
- RAM: 8 GB → 12 GB borderline; marginal — most people won’t notice.
Other makers at the price
Phones from other makers released within a year of the Galaxy S26 and priced within a quarter of its £879, nearest price first, each judged the same way against your Galaxy S21 — or, where that pair is not one this site indexes, against the Galaxy S26.
What yours is worth
Our reading of the figures
The Galaxy S21 stopped receiving security updates on 21 February 2026, so the case for moving is security, not hardware; any of the phones above closes that gap.
The Galaxy S26 clears our noticeable threshold on 3 rows: peak brightness, storage (base), claimed video playback. One more gap is borderline, which most people would not notice. Nothing goes backwards.
At £879 new, less the £116 CeX was paying for a grade A Galaxy S21 on 2026-08-14, the move costs about £763.
Every sentence above is built from the figures on this page by a rule, not written for this phone: a support date, the rows that clear a published threshold, a price and a trade-in. There is no score and no recommendation. The methodology page has the thresholds and where they come from. Every phone’s version of this page is listed at All upgrade questions.