Apple Watch Ultra 4 for Triathletes: Price, Battery and What Changed

Apple announced the Watch Ultra 4 in September 2026 and it reached UK stores on 18 September, starting at £749. It has a 49mm titanium case in natural or black. Apple’s changes are to battery, charging and health sensing. The announcement lists no new swim or multisport features, so the case for a triathlete rests on battery life and whether you already use an iPhone.

What’s new

Battery: up to 50 hours in normal use and 84 hours in Low Power Mode. Extended Workout mode is rated at up to 25 hours and Max Extended Workout mode at up to 45 hours.
Charging: 15 minutes on the charger gives 18 hours of use, according to Apple.
Heart sensor: a new sensing system combines optical and electrical heart sensors. Apple says heart rate is measured every 5 seconds and heart rate variability up to 24 times more often.
Readiness: a daily score from 0 to 10 with recommendations.
Chip and GPS: an S11 chip and dual-frequency GPS.
Display and build: up to 3,000 nits, 100m water resistance and a depth gauge to 40m.
Connectivity: cellular and satellite options on Apple’s product page.

What it means for race day

The workout battery ratings are the useful numbers. IRONMAN gives athletes 17 hours to finish, so a 25-hour Extended Workout rating covers that limit on paper. Apple’s own figures are the only source for these modes so far and we haven’t tested any of them across a race. Long-battery modes usually trade some tracking detail for runtime, so check what each one turns down before you rely on it.

For the swim leg, the watch is rated to 100m of water resistance. watchOS has had a Multisport workout type since watchOS 9, but Apple’s Ultra 4 announcement doesn’t mention changes to it. DC Rainmaker’s in-depth review is the place to read how it performs in practice.

What to check before buying

Your phone. Apple Watch needs an iPhone.
Your sensors. Apple Watch pairs Bluetooth sensors and has no ANT+ radio. An ANT+-only power meter or heart rate strap will not connect.
Your budget. Garmin’s Fenix 9 costs £859.99 at the 47mm size. Our Apple Watch Ultra 4 vs Fenix 9 comparison sets the two side by side, and the best triathlon watches under £300 shows what you can spend a lot less on.

This is launch coverage from Apple’s announcement and published reviews. We haven’t worn the Ultra 4 ourselves.

Available now

Apple sells the Ultra 4 direct and we have no affiliate link for it. If you would rather have a Garmin built around multisport, the Forerunner 970 is on Amazon UK. Read our Forerunner 970 review first.

Check price on Tredz: Garmin Forerunner 970

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