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Key featuresexpand_more

With a long battery life, a super-durable construction and a clear, responsive display, the Forerunner® 255S is a must-have piece of tech for life on and off the track or trail. It provides comprehensive health data such as heart rate, calories, sleep and stress. It also comes with helpful data displays like the morning report which provides a useful overview of your sleep, recovery and training outlook.

30+ activity profiles ensure the Forerunner® 255S can adapt to any training regime, including a dedicated triathlon feature that combines dedicated profiles for running, swimming and cycling. It helps to plan your strategy with daily suggested workouts and syncs up with Garmin IQ, Garmin Connect and other platforms like Strava and Komoot so you can input your pre-planned routes or access routes from other members of the running community.

Advanced running metrics go into more detail than other smartwatches to provide the ultimate training assistance, while helpful features like Garmin Pay™ contactless payments and smartphone notifications ensure the watch provides assiatance in everyday life too.


  • Wrist-based heart rate
  • Stress tracking
  • Sleep score and advanced sleep monitoring
  • Body battery™ energy monitoring
  • Pulse ox
  • Fitness age
  • Intensity minutes
  • Women’s health tracking


  • Morning report
  • HRV status
  • Built-in sports apps
  • Race widget
  • Daily suggested workouts
  • Garmin coach
  • Triathlon and multisport profiles
  • Running power
  • Recovery time
  • Pacepro™ feature
  • Training status
  • Acute load
  • Training effect
  • Performance condition
  • Running dynamics
  • Pre-existing courses
  • Sync routes from other platforms like strava and komoot
  • Track running
  • Visual race predictor
  • Cross-training

Connectivity and Navigation

  • Bluetooth®, ANT+®
  • Smartphone compatibility: iPhone®, Android®
  • Multi-band GNSS support
  • Garmin pay contactless payments
  • Smart notifications
  • Safety and tracking features
  • Livetrack feature
  • Garmin Connect app
  • Connect IQ™ store

Technical specification

  • Water rated to 50 metres (5 ATM)
  • Thermal and shock resistant
  • Fibre-reinforced polymer case
  • Scratch-resistant Corning® Gorilla® Glass 3 screen
  • 18mm QUICKFIT™ compatible watch band
  • Battery: 12 days in smartwatch mode, 26 hours in GPS
  • Weight: 39g
  • Display: 218 x 218 pixels
  • Case size: 41mm
  • Edition: Standard
  • In the box: Forerunner® 255S watch, Charging/data cable, documentation

Delivery & Returnsexpand_more

This product qualifies for the following delivery methods.

Standard Delivery (FREE)

A tracking link will be provided once your order is despatched.

Next Day Delivery (£3.95)

Cannot be offered in the following areas, and will be attempted within 48 hours: BT (all Northern Ireland), GY, IM, JE, KW11-17, HS, PH32-35, ZE.


Returning orders to us is easy. Whatever your reason, we offer a refund or exchange within 28 days of delivery or collection.


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