10 Best Triathlon Watches 2025 in the United States

The Apple Watch Series 10 is a versatile smartwatch that suits many fitness activities, including triathlon training. It offers a bright, larger screen with a lightweight and comfortable design, making it easy to wear all day and during workouts. The watch’s water resistance up to 50 meters means it’s safe for swimming, an essential feature for triathletes. Its GPS supports multiple satellite systems for accurate tracking of your routes in running, cycling, and swimming. Heart rate monitoring is advanced, including ECG capabilities and notifications for irregular heart rhythms, which can be useful for closely monitoring your performance and health.

The multisport mode supports a wide range of activities like running, cycling, swimming, and more, offering detailed workout data and training load insights, helping you improve your fitness effectively. Durability is solid with dust resistance and a crack-resistant screen, suitable for outdoor conditions. Connectivity is strong via Bluetooth, Wi-Fi, and GPS, allowing you to receive calls, messages, and use Siri on the go, but it requires an iPhone to unlock its full potential.

Battery life can last a full day with normal use, which might require daily charging for heavy training days, though fast charging helps recover quickly. The watch also includes innovative safety features like fall and crash detection, adding peace of mind. Compared to some specialized triathlon watches, it may lack longer battery endurance for ultra-distance events and doesn't have built-in cellular connectivity in this GPS-only version. This makes the Apple Watch Series 10 a great fit for triathletes who want a feature-rich, stylish smartwatch that tracks multiple sports with strong health insights and smart connectivity, especially if they already use an iPhone. Those needing very long battery life or a watch focused solely on endurance sports might want to explore dedicated triathlon watches.

The Garmin Forerunner 265 is a strong choice for triathletes thanks to its bright 1.3-inch AMOLED display and a comfortable, lightweight design. It offers solid battery life, lasting up to 13 days in regular smartwatch mode and around 20 hours with GPS active, which is great for long training sessions or races. Its multi-band GNSS with SatIQ technology improves GPS accuracy, especially in tricky environments, helping you track runs, cycling, and open-water swims more reliably.

The watch covers essential triathlon needs with over 30 sport profiles, including triathlon mode, and offers detailed training insights like recovery status, heart rate variability, and training readiness, which can help you train smartly without overdoing it. Heart rate monitoring is well integrated and works alongside other data to give a rounded view of your fitness and effort. Connectivity features include notifications, music control, Garmin Pay for contactless payments, and safety tools like incident detection, but some require your phone nearby and network coverage.

The mix of button and touchscreen controls balances ease of use during active moments. One limitation could be the battery life when GPS is used for very long events, as 20 hours might require charging for ultra-distance triathletes. The Garmin Forerunner 265 is a reliable, feature-rich triathlon watch that combines accurate GPS, useful multisport modes, and smart training tools, making it well-suited for athletes looking to improve performance with detailed insights.

The Apple Watch Ultra 3 is a strong contender for triathletes thanks to its rugged design and comprehensive features. Its titanium case and sapphire crystal display make it highly durable and able to withstand tough conditions, including water resistance up to 100 meters—ideal for swimming and water sports. Battery life is solid, offering up to 42 hours of regular use and up to 72 hours in a low power mode, which is beneficial for long training sessions or races. GPS accuracy is top-notch with dual-frequency support, helping athletes track routes precisely across running, cycling, swimming, and other multisport activities.

The watch also excels in heart rate monitoring, using advanced sensors to provide detailed insights and alerts for unusual heart rhythms or high blood pressure, which can be valuable for health-conscious triathletes. Its multisport mode covers a wide range of exercises, making it versatile for triathlon training and other workouts. Connectivity is excellent, with cellular capabilities allowing calls, music streaming, and emergency satellite messaging even without a phone nearby—great for safety during outdoor adventures.

The watch’s large 49mm size might feel bulky on smaller wrists, and its tight integration with the Apple ecosystem means it works best with an iPhone, which may limit usability for non-Apple users. While the battery life is good, it may still require daily charging for heavy users. This is a premium multisport watch offering robust features and durability, especially suited for athletes who want deep health tracking and reliable connectivity in demanding environments.