Apple Watch Ultra 4 costs $799 and Apple Watch SE 3 costs $249 on Apple’s Store page, a gap of $550. Apple’s tech specs show what that money buys: the S11 chip instead of S10, 50 hours of battery instead of 18, 3000 nits instead of 1000, a 100 m water rating instead of 50 m, a titanium case instead of aluminum, satellite messaging, and the new Health Sensing System with ECG and Blood Oxygen hardware that SE 3 does not have.
They are the two ends of Apple’s lineup, but both run watchOS 27 from September 14, both need an iPhone 11 or later, and both have 5G on cellular models and 64GB of storage. SE 3 briefly went unavailable before the event, but Apple’s Store page lists it from $249 alongside the new models.
Key facts: Ultra 4 vs SE 3
| Spec | Apple Watch Ultra 4 | Apple Watch SE 3 |
|---|---|---|
| Price | From $799, or $24.99 a month | From $249 |
| Case | 49 mm Grade 5 titanium, Natural or Black | 40 mm or 44 mm aluminum, Starlight or Midnight |
| Weight | 63.0 g (Natural), 63.1 g (Black) | 26.3 g (40 mm), 32.9 g (44 mm) |
| Peak brightness | 3000 nits | 1000 nits |
| Chip | S11 | S10 |
| Battery, normal use | Up to 50 hours | Up to 18 hours |
| Low Power Mode | Up to 84 hours | Up to 32 hours |
| Water resistance | 100 m, EN13319 dive to 40 m | 50 m |
| Satellite | Emergency SOS, Messages, Find My | No |
Battery and charging: 50 hours vs 18
Ultra 4 is rated for up to 50 hours of normal use and 84 hours in Low Power Mode, with 18 hours of outdoor workout, 25 hours in Extended Workout and 45 hours in Max Extended Workout. A 15-minute charge gives up to 18 hours and 80 percent takes about 45 minutes. Our Ultra 4 announcement coverage has the full set of Apple’s figures.
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SE 3 is rated for up to 18 hours of normal use and 32 hours in Low Power Mode, and also reaches 80 percent in about 45 minutes according to Apple’s compare page. In practice, an Ultra 4 owner charges roughly every two days where an SE 3 owner charges every day.
| Battery figure | Ultra 4 | SE 3 |
|---|---|---|
| Normal use | Up to 50 hours | Up to 18 hours |
| Low Power Mode | Up to 84 hours | Up to 32 hours |
| Outdoor workout | Up to 18 hours | Not in Apple’s compare rows |
| Fast charge to 80 percent | About 45 minutes | About 45 minutes |
| 15-minute charge | Up to 18 hours | Not in Apple’s compare rows |
Health sensors: the biggest gap
Ultra 4 carries a third-generation electrical heart sensor, an optical heart sensor, a Blood Oxygen sensor, a temperature sensor, a depth gauge and a water temperature sensor. Apple’s Health Sensing System reads heart rate every five seconds and HRV every five minutes, which Apple describes as 60 times and 24 times more frequent than Ultra 3. On top of that sit the Readiness score, ECG, hypertension and sleep apnea notifications and a sleep score.
Apple’s SE 3 tech specs list neither an electrical heart sensor nor a Blood Oxygen sensor, the hardware the ECG and Blood Oxygen apps rely on, so those two apps are the clearest thing $550 buys. Apple’s compare page still lists hypertension notifications and a sleep score for SE 3. Audio Intelligence, meaning Live Rewind, Siri Recap and Sound Recognition, is tied by Apple to the S11 chip’s Secure Exclave; Apple has not said whether any of it reaches the S10-based SE 3.
Display, case and durability
Ultra 4’s display is a flat sapphire crystal over a 422 by 514 pixel Always-On Retina panel with LTPO3, 326 ppi, a 1 Hz refresh floor, 3000 nits peak and a 1 nit minimum. The case is 49 by 44 by 12 mm, tested to MIL-STD 810H, rated IP6X for dust and 100 m for water, with an on-wrist operating range of minus 20 to 55 degrees C.
SE 3 is 40 by 34 by 10.7 mm or 44 by 38 by 10.7 mm in aluminum, peaks at 1000 nits and is rated to 50 m. Apple’s compare rows do not give a resolution or Always-On figure for SE 3. The weight difference is the one you feel: 63 g against 26.3 g or 32.9 g.
Connectivity, satellite and who should pay the difference
Apple’s compare page gives both watches the same Wi-Fi 4, Bluetooth 5.3 and second-generation Ultra Wideband, and 5G on cellular models. Ultra 4 adds precision dual-frequency GPS and satellite for Emergency SOS, Messages and Find My, with two years of service included; Apple’s rows do not specify the GPS type on SE 3.
- Pay $799 if you want ECG, Blood Oxygen, the Readiness score and Apple’s most frequent heart rate sampling, or if you dive, run ultras, or spend time out of cellular range.
- Pay $249 if you want notifications, workouts, 5G calling and sleep tracking on a watch you charge nightly.
- The middle option is Apple Watch Series 12 from $399, which has the same S11 and Health Sensing System as Ultra 4 with a 24-hour battery and a 50 m rating.
What Apple has not said
- SE 3 workout battery hours, 15-minute charge figure, display resolution and GPS type.
- Whether SE 3 gets the Readiness app or any Audio Intelligence feature under watchOS 27.
- Cellular pricing for either watch.
Ultra 4 is on pre-order now and reaches stores on Friday, September 18; SE 3 is listed from $249. Both need an iPhone 11 or later on iOS 27, which arrives as a free update on September 14.
