Apple Watch Ultra 3 vs Apple Watch Ultra 4

Apple Watch Ultra 3 and Apple Watch Ultra 4 are 2025 and 2026 smartwatches from the same product line. This comparison separates the catalog's listed specifications from missing information and approximate values. It covers 17 fields, including 3 exact differences; it does not choose a winner.

Specifications side by side

FieldApple Watch Ultra 3Apple Watch Ultra 4
Release year20252026
Case sizes49 mm49 mm (approx.)
DisplayWide-angle LTPO3 OLED, Always-OnFlat LTPO OLED, Always-On
Brightness3000 nits3000 nits (approx.)
Battery, as listedUp to 42 hours · 72 hours saverUp to 50 hours · 84 hours saver
Operating systemNot listedwatchOS 27
Phone compatibilityiPhoneiPhone
Cellular connectioneSIM · 5GeSIM · 5G
GlassSapphireSapphire
Case materialTitanium (natural/black)Titanium (natural/black)
GPSDual-frequency GNSSDual-frequency GNSS
MapsYesYes
Payment systemApple PayApple Pay
Plan requirementNot requiredNot required
Listed sensors and featuresSleep apnea, ECG, HRV, Readiness score, SpO2, Skin temperatureSleep apnea, ECG, HRV, Readiness score, SpO2, Skin temperature
Safety featuresCrash detection, depth, Fall detection, Satellite SOS, siren, SOS callingCrash detection, depth, Fall detection, Satellite SOS, siren, SOS calling
Hardware flashlightNoNo

"Not listed" means the catalog has no usable value for that field. It does not mean the watch lacks the feature. Approximate values stay visible but do not support the difference count or numeric deltas.

Where they differ

Where they are the same

Which one fits you

Apple Watch Ultra 3 is listed as a smartwatch compatible with iPhone. Start with that phone requirement before comparing the other rows. The exact differences above are a way to identify which listed specifications matter to your use, not evidence that the later generation is better in every respect.

Apple Watch Ultra 4 is listed as a smartwatch compatible with iPhone. Start with that phone requirement before comparing the other rows. The exact differences above are a way to identify which listed specifications matter to your use, not evidence that the later generation is better in every respect.

Information is missing on at least one side for: Operating system. Those rows are excluded from the exact difference count.

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