Apple Watch SE 3 vs Series 9 – Which Should You Buy?

Specs at a Glance

Feature-by-Feature Breakdown

Winner by Category

What They Have in Common

• Design Language: Both watches feature Apple’s recognizable curved rectangular design with an aluminum case, emphasizing comfort and a sleek modern aesthetic. This consistency ensures users experience the same level of premium craftsmanship and familiar interface navigation. It also helps accessories like bands fit seamlessly across models.
• Retina Display: Each model includes a bright Retina display that ensures crisp visuals for text, icons, and animations. The display technology allows easy readability even under direct sunlight. This shared clarity enhances usability in outdoor environments and while on the move.
• watchOS 10 Compatibility: Both run the same watchOS 10 software, meaning users get identical features and updates, including redesigned apps and enhanced fitness tracking. Software consistency allows smooth transitions between devices and ensures long-term support. It also ensures app compatibility across the Apple Watch ecosystem.
• Heart Rate Monitoring: Each watch uses optical heart sensors to track heart rate continuously throughout the day and during workouts. This helps users monitor resting heart rate trends and detect irregular rhythms early. It’s essential for both fitness tracking and preventive health insights.
• Emergency SOS: Both models include Emergency SOS, allowing users to quickly contact local emergency services when needed. This feature can automatically send location data for faster response. It adds significant peace of mind for users engaging in outdoor or solo activities.
• Fall Detection: Both the SE 3 and Series 9 can detect sudden falls and alert emergency services if the user remains unresponsive. This safety feature has proven valuable for older adults and active users alike. It integrates tightly with the accelerometer and gyroscope to ensure accuracy.
• Crash Detection: Each model supports Crash Detection, which recognizes severe car accidents and can automatically call for help. It uses multiple sensors and algorithms to verify impact. This shared capability expands the Apple Watch’s role beyond fitness to personal safety.
• Workout Tracking: Both watches track a wide variety of workouts such as running, swimming, cycling, and yoga with detailed metrics. They encourage daily activity through Move, Exercise, and Stand rings. The shared Workout app makes exercise tracking simple and consistent across devices.
• Water Resistance: Each model is rated for 50 meters of water resistance, making them suitable for swimming in pools or oceans. They can automatically expel water from the speaker after submersion. This feature broadens fitness possibilities without fear of damage.
• Sleep Tracking: Both devices monitor sleep patterns using motion and heart rate sensors. The feature provides insights into sleep duration and quality, helping users build healthier routines. Integration with the Health app enables trend analysis over time.
• Notifications and Calls: Both watches support calls, texts, and app notifications directly on the wrist. Paired with an iPhone, they allow users to respond without needing to reach for their phone. This keeps communication accessible during workouts or when multitasking.
• Apple Pay: Each model includes NFC technology to enable Apple Pay for secure contactless payments. Users can tap their watch at terminals without needing a phone or wallet. It’s fast, private, and convenient for everyday purchases.
• Fitness+ Integration: Both models work seamlessly with Apple Fitness+, allowing guided workouts and metrics synced in real time. The on-screen progress display motivates users to stay active. Whether at home or the gym, this integration enhances the exercise experience.
• Find My and Device Tracking: Both watches integrate with Apple’s Find My network to locate lost devices. They can also ping paired iPhones or AirTags nearby. This shared ecosystem convenience improves device security and everyday organization.

FAQ (Quick Answers)

Does the Apple Watch SE 3 have an always-on display like the Series 9?
No, the SE 3 does not include an always-on display. The screen remains off when not in use to preserve battery life. The Series 9’s always-on Retina display allows users to glance at the time and information without raising their wrist, which adds convenience but slightly impacts battery endurance.

Do both watches have the same chip?
No, the SE 3 runs on the S8 SiP, while the Series 9 uses the more advanced S9 SiP. The newer chip improves responsiveness and supports on-device Siri processing. This leads to faster performance and enhanced dictation accuracy on the Series 9.

Are both models water-resistant?
Yes, both watches have a 50-meter water resistance rating. This means they are suitable for swimming and general water exposure. However, neither is recommended for scuba diving or high-velocity water activities.

Can I track my blood oxygen with the Apple Watch SE 3?
No, only the Series 9 includes a blood oxygen sensor. The SE 3 focuses on core health tracking like heart rate and movement data. Users seeking more advanced wellness metrics would benefit from the Series 9’s expanded sensor suite.

Do both models support sleep tracking?
Yes, both support native sleep tracking through the Sleep app. They analyze motion and heart rate to estimate sleep duration and consistency. The insights help users establish better nighttime habits and track overall wellness trends.

Is ECG available on both watches?
No, the ECG feature is exclusive to the Series 9. It allows users to record an electrocardiogram from the wrist to detect signs of atrial fibrillation. The SE 3 lacks this hardware but still offers valuable heart rate monitoring.

How does battery life compare between the two models?
Both offer up to 18 hours of battery life under typical use. However, real-world performance may vary depending on brightness and workout tracking. The Series 9 can stretch further with optimized usage thanks to its more efficient S9 chip.

Do both support Siri voice commands?
Yes, both support Siri for voice commands, timers, and queries. The Series 9 has the advantage of processing Siri requests directly on-device for faster responses. The SE 3 relies on a network connection for most Siri operations.

Can I use the same watch bands for both?
Yes, both use the same band connector design, making all compatible bands interchangeable. This allows users to reuse existing bands when upgrading or switching models. It enhances the watch’s customization and value over time.

Do both support Apple Fitness+?
Yes, both integrate fully with Apple Fitness+. Users can follow guided workouts while viewing live metrics on-screen. The synchronization between watch and iPhone or Apple TV makes it seamless to track progress.

Can I use Family Setup with either watch?
Yes, both support Family Setup, allowing children or older family members to use a watch without their own iPhone. It enables location sharing, calls, and messages under managed settings. This is especially helpful for families seeking connectivity and safety features.

Are the materials used in both watches the same?
Both models use 100% recycled aluminum for the case and feature Ion-X glass on the display. The sustainability effort aligns with Apple’s environmental goals. Series 9, however, offers additional case finishes and color options.

Do both offer fall detection and crash detection?
Yes, both include these critical safety features. They can detect sudden impacts and contact emergency services automatically if the user is unresponsive. These functions make the watches more than fitness accessories—they’re personal safety devices.

Is GPS available in both?
Yes, both include GPS for route mapping during outdoor activities. The watches can record pace, distance, and elevation without needing an iPhone nearby. This makes them ideal companions for runners, cyclists, and hikers.

Do both watches support Bluetooth and Wi-Fi connectivity?
Yes, both come equipped with Bluetooth and Wi-Fi for seamless connection to iPhones and accessories. These enable syncing of notifications, data transfer, and app updates. The Series 9 also adds the newer Bluetooth 5.3 standard for slightly improved efficiency.

Can I use cellular data on both models?
Yes, both have GPS and GPS + Cellular options. The cellular versions allow calls, messages, and streaming without an iPhone nearby. This is particularly useful for workouts or travel when carrying a phone is inconvenient.

Are both watches compatible with all iPhones?
Both require an iPhone Xs or later running iOS 17 or newer. They pair effortlessly during setup and sync health, fitness, and notification data. Older iPhone models may not support all the latest features.

Do both support Apple Pay?
Yes, Apple Pay works identically on both models using built-in NFC. Users can make secure, contactless payments directly from their wrist. The convenience of leaving a wallet or phone behind adds everyday practicality.

Can I customize the watch faces on both?
Yes, both offer a wide range of customizable watch faces. Users can adjust colors, complications, and styles to match their preferences. This flexibility enhances personalization and makes the watch feel truly individual.

Do both support the Compass app?
Yes, both include the Compass app, offering direction, elevation, and coordinates. It’s particularly useful for outdoor adventures or travel. The app also integrates with Backtrack for retracing steps when off-grid.

Is fast charging supported on both models?
No, only the Series 9 supports fast charging. The SE 3 uses standard charging, which takes longer to reach full battery. Fast charging can be convenient for quick top-ups before workouts or sleep tracking.

Can I use my Apple Watch SE 3 charger with the Series 9?
Yes, the magnetic charging puck works across both models. However, only Series 9 benefits from the faster charge capability. Using existing accessories helps reduce extra costs during an upgrade.

Do both watches measure VO2 Max during workouts?
Yes, both estimate VO2 Max, providing insight into overall cardiovascular fitness. The data appears in the Health app to track aerobic capacity over time. It’s a valuable metric for endurance athletes and those improving their conditioning.

Are both models durable enough for daily use?
Yes, both are built with scratch-resistant glass and aluminum designed for daily wear. They withstand sweat, light impacts, and weather exposure. The durable construction makes them reliable for both active and casual users.