Samsung Galaxy S21 Ultra 5G in 2025: Is It Still Worth Buying?

I’ve been daily driving the Samsung Galaxy S21 Ultra 5G for a few weeks now, and after living with it in 2025, there’s a lot to admire—but also a few things you need to know before considering it. Let’s break down the design, display, battery, camera, performance, and whether this older flagship is still a smart buy today.

Premium Design That Still Turns Heads

The Galaxy S21 Ultra absolutely delivers when it comes to design. It looks and feels like a true flagship, thanks to Gorilla Glass Victus on both front and back, an aluminum frame, IP68 water and dust resistance, and a stunning matte finish. The back feels amazing in the hand, though it can be a bit slippery.

Its rugged, industrial design is striking—but the massive camera module on the rear will divide opinions. Personally, I think it looks sleek and futuristic, especially in the gorgeous Phantom Silver color that beautifully reflects light. However, at 227 grams, it’s heavy and wide, making one-handed use tricky, especially for those with smaller hands.

A notable downside: this was the first Galaxy Ultra without a microSD card slot—Samsung killed expandable storage with this generation. Still, the build quality is top-tier, and you absolutely get what you pay for.

Display: Still One of the Best

Samsung’s display game has always been strong, and the S21 Ultra was no exception. Even by 2025 standards, this 6.8-inch Dynamic AMOLED 2X panel is stunning. It boasts a Quad HD+ resolution and a 120Hz adaptive refresh rate, meaning you no longer have to choose between high resolution or high refresh rate like on older models.

Peak brightness hits 1,500 nits, making it perfectly usable even under direct sunlight—though it won’t quite match newer models like the S25 Ultra. The colors are vibrant, punchy, and simply gorgeous. The adaptive refresh rate can drop as low as 10Hz to save battery, keeping things smooth whether you’re scrolling Reddit, watching YouTube, or gaming.

Simply put, this is one of the best smartphone displays Samsung has ever made, and it still outshines many devices released in 2025.

Battery Life: Solid, But Not Class-Leading

With a 5,000 mAh battery—the same size as today’s S25 Ultra—the S21 Ultra still holds its own. Keep in mind, though, that battery degradation over the years may have affected older units. In my daily use, I’ve averaged about 5 hours of screen-on time with heavy tasks like calls, messages, YouTube, photography, mobile gaming, and Xbox Game Pass. Lighter users could easily push past 6 hours.

Charging speeds, however, feel slow by today’s standards. You get 21W wired charging (about 50% in 30 minutes; a full charge in roughly 1 hour, 15 minutes), 15W wireless charging, and 4.5W reverse wireless charging. Also, Samsung stopped including a charging brick in the box with this model—a decision that’s still frustrating even now.

Cameras: Impressively Capable for 2025

The S21 Ultra’s camera system was ahead of its time and still delivers today. You get:

• 108MP main sensor — improved autofocus, solid low-light performance

• 12MP ultra-wide with autofocus — great for macro shots

• Two telephoto lenses (3x and 10x optical zoom) — offering true optical quality, no marketing tricks

• 40MP front camera with autofocus — still beats many 2025 selfie shooters

Daylight shots are sharp, colorful, and packed with dynamic range. The optical zoom lenses are genuinely useful, and even 10x zoom shots are impressively clear.

Low-light shots without night mode are just okay—sometimes noisy—but with night mode on, the camera excels across all lenses. The only nitpick? Samsung’s processing still leans toward over-sharpening, which can slightly affect fine details when you zoom in.

Performance: Still a Powerhouse

Powered by the Snapdragon 888 or Exynos 2100 (depending on the region), paired with up to 16GB of RAM, the S21 Ultra remains a performance beast. My Snapdragon model with 12GB of RAM runs Android 14 smoothly, with only the occasional lag. Multitasking, gaming, and app launches are snappy, and it easily handles everything from light tasks to Xbox Game Pass.

You can even consider it as a backup gaming phone—it’s that good, even four years later.

Features and Software

The S21 Ultra is feature-packed. You get:

• Ultrasonic under-display fingerprint sensor — fast and reliable

• Facial recognition — decent in good lighting but poor in low light

• Stereo speakers — surprisingly clean and loud

• Samsung Good Lock customization support — including underrated tools like One-Hand Operation

Though it doesn’t come with an S Pen, it supports one, meaning you can use any S Pen from the Note series or newer Ultra models. Just remember: there’s no built-in storage for it.

One important note: software support will end in January 2026, so keep that in mind if you’re planning to use it long-term.

Final Verdict: Still a Strong Contender in 2025

The Samsung Galaxy S21 Ultra 5G remains an excellent smartphone even today. With its premium build, class-leading display, capable cameras, powerful performance, and feature-rich software, it’s a compelling option—especially if you’re looking to buy it used at a discounted price.

It’s not perfect: no microSD slot, slower charging, and upcoming end-of-life software support are valid concerns. But overall, it’s an outstanding device that has aged remarkably well.