Samsung Galaxy S21 Ultra review: specs, battery & used prices

Summary

The Galaxy S21 Ultra is the overachiever of its generation: a 6.8-inch 1,500-nit 120 Hz OLED, a dual-telephoto 108 MP camera system, and the largest battery of the S21 line. Our camera score of 54/100 and screen score of 70/100 are the best in the 2021 cohort — this was Samsung's no-compromise flagship at a $1,200 launch price, and the hardware has aged better than its software support has.

Display and design

The 6.8-inch OLED with a 1,500-nit rating remains excellent: outdoor legibility few 2025 mid-rangers match, adaptive 120 Hz, and the panel that defined Samsung's flagship pitch. At 227 g with IP68, the 65/100 compactness score is the honest tax — this is a big phone, unapologetically.

Performance

Exynos 2100: everyday 69/100, gaming 21/100 — the highest everyday score of the S21 family, aided by the thermal mass of the chassis. Sustained camera and gaming sessions fare better here than on the smaller models.

Camera

The defining feature: a 108 MP main with OIS, 12 MP ultrawide, and a 12 MP telephoto backed by the 2021 flagship's full zoom pipeline, with 8K24 video. The 54/100 score ties the best of its year; low-light main-camera output was class-leading, and the zoom range still covers more than most modern mid-rangers.

Battery and charging

A 5,000 mAh battery at 40/100 with 45 W charging (26/100) — full-day endurance and the family's fastest top-up. The Ultra was the only S21 that charged at more than 25 W.

Verdict

We track essentially no secondhand supply for this model — a thin market for a phone this good, likely because owners keep them. The honest reference is the $1,200 launch configuration; if a listing appears at sensible money, the camera and display still justify it, with the same spent-software-window caveat as the rest of the 2021 generation. The successor S22 Ultra (Snapdragon) trades deeper used supply and the S Pen for a slight camera regroup; the S21 Plus is the cheaper, simpler family alternative.