The Apple Watch Ultra 4 is no longer a rumor. Apple announced it on September 9, 2026, and it started shipping on September 18 at the same $799 the Ultra 3 launched at.
The short version: the case did not change, the chip finally did, and Apple used the new silicon to go after training readiness. Here is the complete picture of what shipped, which rumors died, and where the Ultra still trails Garmin and COROS.
Update, September 11, 2026: the Ultra 4 launched with the S11 chip, a 50-hour everyday battery, a 45-hour per-second GPS mode, new heart sensors, and Apple's Readiness score. Touch ID, microLED, and blood glucose did not make it. Full launch coverage is in our Series 12 and Ultra 4 breakdown.
What Actually Shipped
The S11 chip. This is the headline, and it matters more than it sounds. The Series 11 reused the S10, which was essentially the same silicon as the S9 from 2023. Three generations on one architecture. The S11 breaks that, and it powers the new Health Sensing System. Readiness is tied to the S11 specifically, so Ultra 3 owners will not get it through the watchOS 27 update.
A real battery jump. The Ultra 4 is rated for up to 50 hours of everyday use, up from 42 on the Ultra 3, and 84 hours in Low Power Mode. Fifteen minutes on the charger returns up to 18 hours.
Two new workout modes the Series 12 does not get. Extended Workout tracks with full GPS and heart rate for up to 25 hours, a 25% gain over the Ultra 3. Max Extended Workout stretches runs, walks, and hikes to 45 hours with a GPS reading every second, which Apple says is enough to finish a 100-mile race.
New heart sensors. Optical and electrical heart sensors are new, with a heart rate reading every five seconds and HRV sampled as often as every five minutes. Apple is claiming the most accurate on-device GPS in a sports watch and the most accurate step tracking of any smartwatch, both of which need third-party testing before anyone should take them at face value.
Audio Intelligence. Live Rewind shows the last 15 seconds of a conversation as text after a double press of the Digital Crown. Siri Recap summarizes conversations afterward. Sound Recognition flags sirens, alarms, and doorbells. The audio features arrive in beta later this year.
The Rumors That Did Not Happen
Touch ID. Leaked code pointed at a fingerprint sensor on the watch, and it was the most interesting rumor of the cycle. It did not ship. Apple kept the same side button, Digital Crown, and Action Button layout.
microLED. Apple reportedly shelved its plans for a larger Ultra with a microLED display, and the Ultra 4 uses the same case Apple has run since 2022 in natural and black titanium. Ceramic did return as a case option, but on the Series 12, not the Ultra.
Blood glucose. Still not ready. More on that below.
A design change. The two-year-old case stays. If you wanted a visibly different Ultra, 2027 is the year to watch.
The Battery Picture, With Real Numbers
| Ultra 4 | Garmin Fenix 8 | COROS PACE 4 | |
|---|---|---|---|
| Everyday battery | 50 hours (84 in Low Power) | 28 days | 20 days |
| GPS battery | 45 hours (per-second GPS mode) | 50+ hours | 31 hours |
| Multi-band GPS | Yes | Yes | Yes |
| Recovery score | Yes | Yes | Yes |
| Touch ID | No | No | No |
| Blood glucose | No | No | No |
| Maps | Yes | Yes | Yes |
The GPS number is the one that matters for endurance athletes, and it is the one Apple improved most. Forty-five hours of second-by-second GPS is a different category of watch than the 20-hour Ultra 2.
It is still not a Garmin. A Fenix 8 runs weeks between charges in normal use, and the Ultra 4 runs days. Apple has never tried to win that fight, and it still is not trying. What changed is that the Ultra is no longer disqualified from the events Garmin owners plan their seasons around.
The Blood Glucose Question
Blood glucose is the white whale of wearable health tracking, and it is worth understanding why a decade of work has not produced a shipping product.
Apple has been at non-invasive glucose monitoring since roughly 2010. The prize is obvious: millions of people with diabetes could track blood sugar without a finger prick. The obstacle is physics. Glucose molecules are small, and detecting them through skin and fat means reading an extremely subtle signal through hydration changes, skin temperature, and motion.
Every major tech company is working on it, including Samsung and Google. None has cracked it to a standard that regulators would accept. Apple reportedly has prototypes working in a lab, which is not the same as a product.
The Ultra 4 does not have it. The Ultra 5 or Ultra 6 might. When it lands, it will be the biggest health feature in wearable history, and it will not be an incremental update.
What Is Still Unclear
- Whether Readiness reaches older watches. It is tied to the S11 chip, so Ultra 3 and Series 11 owners are currently locked out.
- How the GPS claims hold up. Apple's accuracy claims are strong, and the independent testers who have spent years benchmarking Garmin and COROS will be the ones who settle it.
- Whether the battery gains keep coming. Apple could put future efficiency gains into new sensors instead of more runtime.
- What happens with satellite. Satellite messaging is unchanged this year, still free for two years from activation on Globalstar. Nothing new was added despite the rumors.
The Bottom Line
The Ultra 4 is the first Ultra upgrade that changes what the watch is for. The chip stopped being a rebadge, the battery finally crossed into multi-day territory, and Readiness turns it into a recovery tracker that competes with Garmin and Whoop instead of just counting rings.
If you own an Ultra 2, the move to 50 hours of normal use, 45 hours of per-second GPS, and the new heart sensors is the most substantial Ultra upgrade Apple has shipped. If you own an Ultra 3, you are getting better battery and the new sensors, but you are locked out of Readiness, which is the single most interesting feature of this cycle.
For anyone weighing it against a Garmin, the honest read is that Apple closed the gap that mattered most and left the rest alone. It is a better sports watch than the Ultra 3 by a wide margin. It is still not a Fenix.
Sources: Apple's September 9, 2026 event, BGR's hands-on breakdown of the Series 12 and Ultra 4, Macworld's launch guide, PhoneArena's spec coverage, and Apple's Ultra 3 battery specifications for comparison.