Published 2026-04-17 by James Maxwell

Both the Apple Watch Ultra 3 and Samsung Galaxy Watch Ultra are excellent fitness smartwatches, but they suit very different buyers. The Apple Watch Ultra 3 is the better choice if you’re on iPhone and want the most accurate health tracking available, while the Samsung Galaxy Watch Ultra makes more sense for Android users who want comparable hardware at a slightly lower price.

We’ve been tracking both watches since launch, and the gap between them is small in hardware terms. That makes the buying decision almost entirely about ecosystem, price, and which one fits your wrist.

These are the two most capable consumer smartwatches you can buy in the UK right now. The Apple Watch Ultra 3 is Apple’s flagship wearable, sitting well above the Apple Watch Series 10 (from around £399) in both price and specification. The Samsung Galaxy Watch Ultra is Samsung’s answer to it, launched in 2024 and still competitive heading into 2026.

The Apple Watch Ultra 3 starts at £623.99 in the UK, based on Shopping.co.uk price tracking at the time of writing. OnBuy.com currently has the 49mm Black model at £630.99, with the lowest price we’re tracking sitting at £623.99. Compare current offers on shopping.co.uk.

The Samsung Galaxy Watch Ultra launched at £649 in the UK but has since dropped to around £499 at major retailers including Amazon and John Lewis, making it the cheaper option right now despite being the “rival flagship.” That price drop reflects Samsung’s typical pattern: significant discounts within 6 to 12 months of launch.

Apple Watch Ultra pricing holds much more stubbornly. The Ultra 2 was still selling close to its launch price 6 months after release, and the Ultra 3 looks set to follow the same pattern. If you’re hoping to wait for a sale, the Samsung is the safer bet for a price drop. The Apple Watch Ultra 3 is unlikely to see reductions before autumn 2026.

In real-world testing, both watches perform closely on step counting and heart rate, but Apple has a slight edge on consistency. According to testing by Tom’s Guide (April 2026), a 6,500-step walk produced near-identical step counts from both devices, with the difference falling within normal margin of error.

Where Apple pulls ahead is in sleep tracking refinement and the depth of its Health app data. The Ultra 3 adds new mental health logging and a trained detection system for atrial fibrillation that has received CE marking for medical use in the EU.

Samsung counters with its BioActive Sensor, which combines optical heart rate, electrical heart, and bioelectrical impedance sensors in one unit. This gives the Galaxy Watch Ultra body composition tracking (body fat percentage) that the Apple Watch Ultra 3 doesn’t offer.

For runners and cyclists, both watches support dual-frequency GPS (L1 and L5), which means accurate route tracking even in urban canyons. Neither has a significant advantage here.

The Apple Watch Ultra 3 lasts up to 72 hours in low-power mode, or around 36 hours with the always-on display active, per Apple’s published specs. The Samsung Galaxy Watch Ultra reaches up to 60 hours in power-saving mode.

Day-to-day, both watches comfortably cover two days of regular use without a charge. The Ultra 3’s titanium case and sapphire crystal are rated to 100m water resistance. Samsung’s watch is rated to 10ATM (also 100m) with a similar titanium build.

The Apple Watch Ultra 3 is heavier at 61.4g versus Samsung’s 60.5g — a negligible difference in practice. Both are large watches. If you have a smaller wrist, neither will look understated.

One practical limitation: the Apple Watch Ultra 3 is currently only listed in Black through UK retailers tracked by Shopping.co.uk. Other colour and band options may have more limited availability or higher prices.

This is where the decision is effectively made for most buyers. The Apple Watch Ultra 3 only works with iPhone. Full stop. If you own a Samsung, Google Pixel, or any other Android phone, the Apple Watch Ultra 3 is simply not an option.

The Samsung Galaxy Watch Ultra works best with Samsung Android phones, where you get full health data sync, SmartThings integration, and Samsung Pay. It works with other Android phones too, though some features are restricted. It does not work with iPhone.

If you’re an iPhone user, the Apple Watch Ultra 3 is the stronger choice on pure integration depth. Handoff between watch and phone, Apple Pay, emergency SOS via satellite, and Siri integration all work more smoothly than any third-party alternative.

At £623.99, the Apple Watch Ultra 3 is £124 more expensive than the Samsung Galaxy Watch Ultra’s current street price of around £499, and that gap is hard to justify on hardware alone.

Best place to buy: OnBuy.com , currently listing the 49mm Black model at £630.99 with the lowest tracked UK price sitting at £623.99 at time of writing; worth checking Shopping.co.uk for any further movement across retailers.

vs. Samsung Galaxy Watch Ultra: Samsung has dropped around £150 from its launch price in under 18 months, making it the better value buy on hardware right now. The Apple Watch Ultra 3 holds its price, which means iPhone users are paying a premium for ecosystem integration rather than superior sensors.

Our take: Buy the Apple Watch Ultra 3 if you’re committed to iPhone and want the deepest health data integration available; if you’re on Android or price-sensitive, the Samsung Galaxy Watch Ultra at ~£499 does 90% of the same job for significantly less.

Does the Apple Watch Ultra 3 work with Android phones?
No. The Apple Watch Ultra 3 requires an iPhone running iOS 17 or later. It cannot be paired with any Android device.

Is the Apple Watch Ultra 3 worth upgrading from the Ultra 2?
The Ultra 3 adds updated health sensors and Apple Intelligence features, but the core hardware and design are similar to the Ultra 2. If you own an Ultra 2, the upgrade is hard to justify at full price. If the Ultra 2 drops significantly (it was retailing around £549 in early 2026), that may be the smarter buy.

Which watch is better for swimming?
Both are rated to 100m water resistance, and both support open-water swim tracking. The Apple Watch Ultra 3 has a slightly longer track record with competitive swimmers, but the Samsung Galaxy Watch Ultra’s 10ATM rating covers the same real-world use cases.

Where is the cheapest place to buy the Apple Watch Ultra 3 in the UK?
At the time of writing, Shopping.co.uk is tracking the Apple Watch Ultra 3 (49mm Black) from £623.99. Prices can shift quickly, so compare current offers here.

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