Apple Watch Ultra 3

Ultra 3 went on sale on 19 September 2025. A year later Apple put the same case and screen around new heart sensors and a longer-lasting battery and called it Ultra 4, which leaves a discounted Ultra 3 with almost everything that makes the current Ultra an Ultra.

What Ultra 4 adds

Spec	Ultra 3	Ultra 4
Announced	9 September 2025	9 September 2026
Case	49mm Grade 5 titanium	Same
Weight	61.6 g natural; 61.8 g black	63.0 g natural; 63.1 g black
Screen	422 × 514 LTPO3, 3,000 nits	Same
Chip	S10	S11
Heart sensors	Third-generation optical + electrical	Health Sensing System
Normal use	Up to 42 hours	Up to 50 hours
Low Power Mode	Up to 72 hours	Up to 84 hours
Max Extended Workout	No	Up to 45 hours (outdoor run, walk or hike)
15-minute charge	About 12 hours	About 18 hours
Satellite, 40m dive, Action Button	Yes	Yes
US launch price	$799	$799

The case, the 3,000-nit screen, the Action Button, the dive gear, dual-frequency GPS and satellite are all shared. The differences are inside.

Heart sensors. Ultra 4’s Health Sensing System checks your heart rate in the background every five seconds, which Apple calls 60× more often than Ultra 3, and samples heart rate variability 24× more often. Ultra 3 keeps the third-generation optical sensor and the electrical sensor, so it still covers ECG, Blood Oxygen and the sleep and hypertension features below.

Battery. Ultra 4 runs eight hours longer in normal use (50 against 42) and 12 hours longer in Low Power Mode (84 against 72). It also adds Max Extended Workout for long GPS days on foot.

Chip. S11 brings Audio Intelligence to Ultra 4; Ultra 3’s S10 doesn’t get those features.

If none of that changes your day, Ultra 3 is the better deal whenever it’s clearly cheaper. Ultra 4 vs Ultra 3 goes through the rest.

The screen Ultra 4 kept

This is the display Apple carried into Ultra 4: a 3,000-nit Always-On LTPO3 Retina under flat sapphire, 422 × 514 pixels at 326 ppi, dimming to 1 nit in the dark, with wide-angle OLEDs. Night Mode works on the Modular Ultra, Wayfinder and Orienteering faces.

The change from Ultra 2 is Always On. It refreshes at 1Hz, so the dimmed face updates once a second: a seconds hand keeps sweeping and the Stopwatch and Timer keep counting without a wrist raise. Ultra 2 and earlier updated Always On about once a minute. Coming from the original Ultra, which peaks at 2,000 nits on a 410 × 502 screen, you also get a brighter display with more pixels.

Battery and charging

Mode	Ultra 3
Normal use	Up to 42 hours
Low Power Mode	Up to 72 hours
GPS workouts	Not published
Fast charge	About 80% in 45 minutes; 15 minutes for about 12 hours; 5 minutes for about 8 hours of sleep tracking

Short top-ups go a long way: 15 minutes on the charger buys about 12 hours of normal use, and 5 minutes covers about 8 hours of sleep tracking, enough for a night. Ultra 4 stretches those to about 18 and 10 hours. The Magnetic Fast Charger to USB-C cable (1m) comes in the box.

Health and sleep

Ultra 3 has the third-generation optical heart sensor and the electrical heart sensor for the single-lead ECG app, plus Blood Oxygen, a wrist temperature sensor, Cycle Tracking and hypertension notifications. The Sleep app tracks stages, gives you a Sleep score and can flag possible sleep apnea.

It doesn’t sample your heart as often as Ultra 4, but if ECG and sleep data are what you use, you won’t miss much.

Satellite, diving and the outdoor kit

• Satellite: Emergency SOS, Messages and Find My work where there’s no cell signal; coverage and iPhone pairing limits apply.
• Water and diving: water resistant to 100m (WR100 under ISO 22810:2010) and certified to EN 13319 for recreational scuba to 40m, with the depth gauge accurate to about 1m. A dive computer app such as Oceanic+ opens automatically at 1m, and GPS marks where you went in and came out.
• Dust and knocks: IP6X dust protection, and tested to a list of MIL-STD-810H methods: altitude, heat and cold, temperature shock, immersion, freeze and thaw, ice and freezing rain, shock and vibration.
• Controls and alarms: the Action Button, which can start a workout with Precision Start, plus a siren and a flashlight.
• Navigation: L1 and L5 dual-frequency GPS, a compass with bearing, incline, elevation and coordinates, automatic waypoints where you last had a cell signal, Backtrack, offline maps with custom routes, and U.S. topographic maps with curated hikes in all 63 U.S. national parks.

Apple rates it for −20°C to 55°C on the wrist, dives in water from 0°C to 40°C, and altitudes from −500m to 9,000m. Fall Detection, Crash Detection, Emergency SOS, Check In and noise monitoring aren’t Ultra-only; Series watches have them too.

Workouts

Ultra 3 has the same five dedicated workout sets Ultra 4 later kept. Running adds form and power metrics (cadence, stride length, ground contact time, vertical oscillation, running power), Race Route, Pacer and VO2 max, and it detects tracks automatically. Cycling works with Bluetooth power meters and Functional Threshold Power, swimming tracks SWOLF and kickboard sets, and diving logs depth and water temperature. Skiing, snowboarding, outdoor rowing, paddling and golf are on the list too.

Software and iPhone

Ultra 3 launched on watchOS 26 and gets watchOS 27. Apple doesn’t say how many years of updates it will get. Double tap and wrist flick give you one-handed control. Ultra 3 is model A3281, with 5G RedCap and LTE cellular and international roaming, plus Wi-Fi 4, Bluetooth 5.3, a second-generation Ultra Wideband chip, Apple Pay and GymKit.

Price and what’s in the box

Ultra 3 launched at $799 in the US on 9 September 2025, and Ultra 4 replaced it at the same price a year later. A new Ultra 3 only makes sense below that, and what’s left is priced differently from one retailer to the next, so check before you buy.

The box has the watch, one band and the Magnetic Fast Charger to USB-C cable (1m). Bands use Apple’s Ultra fitting rather than a standard 22mm quick-release. Apple says Ultra 3 is made with 40% recycled content, including all of the titanium in the case.