The honest divide in running watches in 2026 is between watches built around running data and smartwatches that happen to track running. The Garmin Forerunner is the first kind. The Apple Watch is the second. For most adults running occasionally, the Apple Watch is fine. For anyone training for a specific race — half marathon, marathon, ultra — the Garmin's training metrics genuinely change how you train, and the Apple Watch doesn't.
This is the slightly contrarian thing to say in 2026 because Apple Watch Ultra 2 is now genuinely capable for runners. Battery is 3-4 days (up from a single day on regular Apple Watches), the running apps via the App Store cover most gaps, and if you live in the Apple ecosystem the integration is real. But Garmin's training readiness, race predictor, and recovery metrics aren't matched by Apple's equivalents. For serious runners, the Garmin still wins.
We tested three across 200km each by a UK marathon-training runner: Garmin Forerunner 265, Apple Watch Ultra 2, and Coros Pace 3.
How to pick by your running
Serious UK runner training for races: Garmin Forerunner 265 at £400-£480 (or 965 for triathlon).
Triathlete / multi-sport: Garmin Forerunner 965 or Apple Watch Ultra 2.
Apple ecosystem deep, race occasionally: Apple Watch Ultra 2.
Value pick, serious training features: Coros Pace 3 at £230-£280.
For most serious runners: Garmin Forerunner 265 at £400-£480. Best balance of training features, battery life, and price.
The three worth knowing
Garmin Forerunner 265 at £400-£480. What most marathon-training runners are using in 2026. Multi-band GPS, full training metrics (training readiness, race predictor, recovery), 13-day battery in smartwatch mode, ~24 hours in GPS mode.
What's good: best training metrics in the category — Garmin's algorithms are genuinely useful, not marketing window-dressing. Multi-band GPS is accurate even in built-up cities. 13-day battery versus Apple Watch Ultra's 3-4 days. Strong third-party app ecosystem (Strava, TrainingPeaks, etc.). Sleep tracking is competitive.
What's not good: £450 is meaningful. Garmin app is improving but trails Apple Health for general health context.
Apple Watch Ultra 2 at £799-£899. Apple's premium watch with sport-focused features. For runners deep in the Apple ecosystem who only run occasional races, the Ultra 2's battery is now adequate where the regular Apple Watch's wasn't. Training apps via the App Store cover the gaps. Best for runners who want one watch that does everything (smartwatch + serious running) and don't mind the price.
Coros Pace 3 at £230-£280. Value pick. Serious training metrics, reasonable price, much smaller UK presence than Garmin. The right answer for runners on tight budgets who want serious training features.
How I'd actually pick
UK adults running 30km-plus per week: Garmin Forerunner 265. The training metrics genuinely help.
Runners on tight budgets: Coros Pace 3 at £250.
Apple-ecosystem deep users who run occasionally: Apple Watch Ultra 2 if budget allows; Garmin Forerunner 265 if you'd prefer better training metrics regardless of ecosystem.
What I'd swerve: budget Garmins (Forerunner 55 at £170) — the savings versus the 265 don't justify the missing features for serious runners. If you're not going to use the training metrics, save more and buy the Coros.
A note on what the metrics actually tell you
Training readiness, recovery scores, race predictors — these aren't magic. They're estimates based on heart rate variability, sleep, recent training load, and a few other inputs. They get things wrong. But they get them wrong in informative ways: a "low recovery" reading after a hard week is worth treating seriously, even if you feel fine. The watches that have this — Garmin and Coros — make it harder to over-train, which is the most-common mistake serious runners make.
The Apple Watch Ultra has equivalents but they're less mature. Use the watch you have; just be aware of the gap.
Affiliate disclosure: Morningfold has affiliate partnerships with Garmin, Apple, and Coros. See editorial standards.