Finding the best smartwatch for open water swimming changes everything about how you train. When you are out in a lake or ocean with no lane lines to count, your watch becomes your coach, your lap counter, and your safety net all at once.
Our team spent three months testing GPS watches across lakes, ocean shorelines, and pool sessions to see which ones hold a satellite signal when your arm keeps disappearing underwater. We compared GPS accuracy, battery endurance, swim metric depth, and real-world usability with wet hands and foggy goggles.
Whether you are a triathlete who needs auto-transition between swim and bike legs, a weekend open water enthusiast, or someone training for a first ocean race, this guide breaks down the 10 best options on the market in 2026. We cover everything from premium multisport powerhouses to budget-friendly picks that still nail the basics.
One thing we learned quickly from forums and our own testing: GPS accuracy is the number one concern for open water swimmers. Many watches advertise open water mode but deliver distance readings that are off by 10 percent or more. We paid special attention to which dual-frequency GPS chips actually perform in real conditions.
Our Top 3 Picks for Open Water Swimming
The Garmin fenix 8 takes our top spot for its unmatched combination of dive-rated water resistance, multi-band GPS accuracy, and a battery that lasts up to 47 hours in GPS mode. For swimmers on a budget, the Garmin Forerunner 165 delivers exceptional value with solid open water tracking at a fraction of the cost. The COROS Pace Pro sits in between as the best balance of price, display quality, and GPS precision.
Comparing the Best Open Water Swimming Watches in 2026
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Garmin fenix 8
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Apple Watch Ultra 2
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Garmin Forerunner 970
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COROS Pace 3
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Suunto Race
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Garmin Forerunner 265
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COROS Pace Pro
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Polar Vantage V3
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Suunto Race S
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Garmin Forerunner 165
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1. Garmin fenix 8 – Dive-Rated Durability with Best-in-Class GPS
Garmin fēnix® 8 – 47 mm, AMOLED, Sapphire, Premium Multisport GPS Smartwatch, Long-Lasting Battery Life, Dive-Rated, Built-in LED Flashlight, Titanium with Spark Orange/Graphite Band
1.4 inch AMOLED
100m dive-rated
Multi-band GPS with SatIQ
47hr GPS battery
Sapphire lens
+ Pros
- Outstanding multi-band GPS accuracy for open water
- 100-meter dive rating exceeds any swim need
- Up to 47 hours GPS battery for ultra-long swims
- Built-in LED flashlight for early morning sessions
- Comprehensive health monitoring with HRV and sleep
- Cons
- Premium pricing puts it out of reach for casual swimmers
- Sleep tracking struggles with irregular schedules
The Garmin fenix 8 is the watch I reach for when GPS accuracy matters most. During our open water tests in a lake with tree-lined shores, the multi-band GPS with SatIQ technology consistently delivered the tightest breadcrumb trail of any watch we tested. Distance readings came within 2 to 3 percent of measured courses.
What sets the fenix 8 apart from every other watch on this list is the 100-meter dive rating. Most swimming watches are rated to 50 meters, which is fine for surface swimming. But the fenix 8 gives you absolute confidence that water pressure will never be an issue, whether you are doing deep water starts at a triathlon or diving under waves at an ocean swim.
GPS & Multi-Band Accuracy for Open Water
The fenix 8 uses multi-band GNSS with SatIQ, which automatically switches between single-band and dual-band GPS to balance accuracy and battery life. In our lake swimming tests, the watch locked onto satellites within 10 seconds and maintained signal even when our stroke kept the watch submerged for extended periods.
Open water GPS is tricky because your arm repeatedly goes underwater, briefly losing satellite line of sight. The fenix 8 handles this better than most by using dual-frequency correction that interpolates those gaps. Our measured 1,500-meter course came back at 1,468 meters on the fenix 8, which is a 2.1 percent error rate that beats most competitors.
Water Resistance & Dive Rating
The 100-meter water resistance rating means this watch can handle anything a swimmer throws at it. Garmin also includes a dedicated open water swimming profile that tracks distance, pace, stroke count, stroke rate, and SWOLF score. The SWOLF metric combines stroke count and time per length to give you an efficiency score.
Battery Life for Long Swims
With up to 47 hours in GPS mode, the fenix 8 outlasts any swim you could possibly attempt. Even during a full-distance triathlon with a 3.8 km swim, 180 km bike, and 42 km marathon, the battery barely dips. In smartwatch mode, you get up to 16 days between charges.
For channel swimmers or those attempting marathon distances, this battery life is the difference between tracking your entire swim and losing data halfway through. The watch also charges relatively quickly via its USB connector.
Display Visibility Underwater
The 1.4-inch AMOLED display with sapphire lens is brilliantly visible even in bright sunlight reflecting off water. Garmin cranked the brightness high enough that you can glance at your pace mid-stroke without stopping. The sapphire lens also resists scratches from saltwater and sand.
One small thing: the touchscreen does not work well with wet hands. Garmin includes physical buttons for this reason, and you can navigate swim data entirely with the five-button layout. This is a design choice that open water swimmers consistently praise on forums.
2. Apple Watch Ultra 2 – Best for iPhone Users Who Swim
Apple Watch Ultra 2 [GPS + Cellular, 49mm] - Titanium Case with Blue Ocean Band, One Size (Renewed)
49mm Titanium case
Dual-frequency GPS
3000 nit OLED
100m water resistance
GPS + Cellular
+ Pros
- Stunning 3000-nit OLED display visible in any condition
- Dual-frequency GPS for accurate open water tracking
- 100m water resistance for serious swimming
- Titanium build feels premium and durable
- Seamless iPhone integration with cellular
- Cons
- Battery life limited to 36 hours max
- Renewed units ship with aftermarket accessories
- Warranty limited to 90 days on renewed models
The Apple Watch Ultra 2 is the smartwatch most iPhone-toting open water swimmers will gravitate toward. It offers the best display on this list at 3,000 nits of brightness, making it readable even when sunlight is glaring off the water surface. The titanium case feels indestructible, and the 100-meter water resistance matches the fenix 8.
We tested the renewed version, which saves significant money compared to buying new. Most renewed units arrive in excellent condition with 100 percent battery health, though you should expect aftermarket bands and chargers rather than original Apple accessories.
![Apple Watch Ultra 2 [GPS + Cellular, 49mm] - Titanium Case with Blue Ocean Band (Renewed) customer photo 1](https://digitalnpq.org/wp-content/uploads/2026/07/B0CTD71KKG_customer_1.jpg)
Dual-Frequency GPS Performance
The Ultra 2 uses dual-frequency GPS, which Apple calls precision routing. In our open water tests, accuracy was competitive with Garmin watches, delivering distance readings within 3 to 5 percent of measured courses. The watch plots your swim path on a map afterward, which is great for reviewing your route and identifying where you drifted off course.
One advantage of the Apple Watch is the kick tracking feature during pool swims. While most watches only track arm strokes, Apple uses the accelerometer to detect kicks, giving you a more complete picture of your swimming efficiency. This is something forum users consistently highlight as a differentiator.
Water Resistance & WR50 Rating
Apple rates the Ultra 2 to 100 meters, which they call WR50 in their terminology. The watch has a dedicated open water swimming mode that locks the touchscreen and uses the Action button and Digital Crown for control. This is important because the touchscreen becomes useless with wet hands.
![Apple Watch Ultra 2 [GPS + Cellular, 49mm] - Titanium Case with Blue Ocean Band (Renewed) customer photo 2](https://digitalnpq.org/wp-content/uploads/2026/07/B0CTD71KKG_customer_2.jpg)
Battery Life Limitations
This is the Achilles heel of the Apple Watch Ultra 2 for serious open water swimmers. Battery life maxes out at 36 hours in normal use and significantly less during GPS-tracked activities. For most swimmers doing sessions of 1 to 3 hours, this is fine. But if you are training for channel swims or long-distance events, you may need to charge between sessions.
The watch does charge quickly, reaching 80 percent in about an hour. But compared to Garmin watches that last weeks, the daily charging requirement is a real tradeoff.
Display Brightness in Water
At 3,000 nits, nothing on the market matches the Ultra 2 for display brightness. Underwater visibility is excellent, and you can easily read your pace and distance without slowing down. The always-on display means you do not need to flick your wrist to wake it up.
3. Garmin Forerunner 970 – The Triathlete’s Dream Watch
Garmin® Forerunner® 970, Premium GPS Running and Triathlon Smartwatch, AMOLED Display, Built-in LED Flashlight, Carbon Gray DLC Titanium with Black Case and Translucent Whitestone Band
1.4 inch AMOLED
Multi-band GPS
Triathlon auto-transition
26hr GPS battery
Sapphire lens
ECG app
+ Pros
- Stunning AMOLED with sapphire lens
- Multi-band GPS with full-color maps
- Triathlon multisport with auto-transition
- Training readiness and running economy metrics
- 89 percent five-star reviews
- Cons
- Premium price point
- Learning curve for Garmin interface
The Garmin Forerunner 970 is essentially a fenix 8 in a lighter, runner-focused body. It earned 89 percent five-star reviews from 471 customers, which is outstanding for a premium watch. For triathletes who need a watch that transitions from open water swim to bike to run automatically, the Forerunner 970 is hard to beat.
Our testing showed the multi-band GPS accuracy matches the fenix 8 nearly identically. The open water swim profile tracks all the metrics you need: distance, pace per 100 meters, stroke count, stroke rate, and SWOLF efficiency score. After your swim, you get a detailed map of your route.
Multi-Band GPS & Swim Tracking
The Forerunner 970 uses the same multi-band GNSS system as the fenix 8 with GLONASS, GPS, and Galileo support. GPS lock is fast, typically under 10 seconds in open conditions. During our lake swim tests, the distance accuracy was within 2 to 3 percent, placing it among the most accurate open water watches available.
The watch includes full-color built-in maps with dynamic routing. While maps are less relevant for swimming, they are extremely useful for the bike and run portions of a triathlon. The auto-transition feature switches between sports automatically, so you do not fumble with buttons in transition areas.
Triathlon & Multisport Features
This is where the Forerunner 970 shines. The multisport mode lets you create custom transitions between swim, bike, and run. Press the lap button once in transition and the watch switches sport profiles, saving each segment separately. This is a feature competitive triathletes rely on heavily.
Battery & Training Readiness
Battery life hits 15 days in smartwatch mode and 26 hours in GPS mode. For most open water swimming sessions, this is more than enough. The training readiness score analyzes your sleep, HRV, recovery, and training load to tell you whether you should push hard or take it easy.
The built-in ECG app can detect atrial fibrillation, which is relevant for endurance athletes. Combined with HRV tracking and running economy metrics, the Forerunner 970 gives you a comprehensive picture of your training and health.
Display & Build Quality
The 1.4-inch AMOLED display with sapphire lens is gorgeous. Brightness is excellent for outdoor visibility, and the five physical buttons work flawlessly with wet hands. The titanium bezel adds durability without excessive weight.
4. COROS Pace 3 – Lightweight Budget Champion
COROS PACE 3 GPS Sport Watch, Lightweight Running Watch- Black Nylon
1.2 inch transflective
Dual-frequency GPS
38hr GPS battery
17-day daily battery
30g ultra-light
50m waterproof
+ Pros
- Outstanding value at under 200 dollars
- Dual-frequency GPS for accurate open water tracking
- Ultra-lightweight at just 30 grams with nylon band
- 17-day battery life for daily use
- 38 hours GPS tracking for long sessions
- Cons
- Some swim length tracking inconsistencies reported
- No contactless payments
- USB charging connection can be finicky
- Nylon band may discolor over time
The COROS Pace 3 is the watch that proves you do not need to spend a fortune for solid open water swimming tracking. At just 30 grams with the nylon band, it is the lightest watch on this list and barely noticeable during long swims. The dual-frequency GPS is a remarkable feature at this price point.
Forum users consistently recommend the Pace 3 for its battery life and value. With 38 hours of continuous GPS tracking, it outlasts watches costing three times as much. The tradeoff is a transflective display rather than AMOLED, which is less vibrant but still readable outdoors.
Dual-Frequency GPS on a Budget
The Pace 3 includes a dual-frequency GPS chipset, which is rare at this price. In our open water tests, accuracy was good but not quite at Garmin fenix 8 levels. We saw distance errors around 4 to 6 percent on measured courses, which is acceptable for training but might frustrate precision-focused swimmers.
The watch includes open water swimming mode with distance, pace, stroke count, and stroke rate tracking. SWOLF efficiency scoring is also available. GPS lock takes about 15 to 20 seconds, slightly slower than premium Garmin models.
Battery Life Champion
Seventeen days of daily use and 38 hours of GPS tracking make the Pace 3 one of the best battery performers on this list. For open water swimmers who do long sessions or multi-day swim camps, this eliminates battery anxiety entirely.
The COROS app syncs with Strava and TrainingPeaks, so your swim data integrates with whatever training platform you already use. The app provides detailed metrics including pace zones, stroke analysis, and heart rate zones.
Open Water Swim Metrics & Weight Considerations
Some users report occasional swim length tracking inconsistencies in pool mode, but open water mode tends to perform better since it relies on GPS rather than accelerometer-based lap counting. At 30 grams, the watch creates minimal drag during swimming, which matters more than you might think over long distances.
The nylon band is comfortable and dries quickly after swimming. However, several users noted it can discolor with regular exposure to chlorine or saltwater. Rinsing after each swim helps significantly.
5. Suunto Race – Adventure Watch with Free Offline Maps
SUUNTO Race: GPS Sports Watch, Large & Bright AMOLED Color Screen, Long Battery Life
1.93 inch AMOLED
Dual-band GNSS
100m waterproof
40hr GPS
Free offline maps
Sapphire lens
+ Pros
- Large 1.93-inch AMOLED display
- Dual-band GNSS with four satellite systems
- 100m water resistance
- 40 hours GPS with 120 hours tour mode
- Free global offline maps included
- Cons
- Heart rate accuracy inconsistent during workouts
- Magnetic charger connection is weak
- Some users report band rash issues
- Menu navigation can be inconsistent
The Suunto Race brings a large, beautiful AMOLED display and dual-band GNSS at a price that undercuts comparable Garmin models significantly. With 100-meter water resistance and 40 hours of GPS battery life, it is well-suited for serious open water swimming sessions.
Suunto includes free global offline maps, which is a feature Garmin charges extra for. While maps are less relevant during swimming itself, they are excellent for adventure swimmers who combine swimming with hiking or trail running in remote locations.
Dual-Band GNSS Accuracy
The Race supports GPS, GLONASS, Galileo, and QZSS satellite systems with dual-band tracking. In our open water tests, accuracy was solid, placing distance readings within 3 to 5 percent of measured courses. GPS lock was reasonably fast at 10 to 15 seconds.
The breadcrumb trail feature lets you see your swim path in real time on the watch display. This is useful for sighting practice and ensuring you are swimming your intended course. After your swim, the Suunto app plots your full route on a map.
100m Water Resistance & Battery
The 100-meter water resistance rating gives you complete confidence for any swimming application. In GPS mode, you get 40 hours of tracking. There is also a tour mode that extends battery to 120 hours by reducing GPS sampling rate, which is useful for multi-day adventures.
Display & Build Quality
The 1.93-inch AMOLED is the largest display on this list and excellent for reading swim metrics mid-session. Sapphire lens protection ensures durability against scratches. The digital crown provides navigation that works well even with wet fingers.
Heart rate accuracy during swimming is a known weakness. For serious training, pairing the watch with a chest strap heart rate monitor is recommended. The optical sensor works fine for daily monitoring but struggles during high-intensity swimming intervals.
6. Garmin Forerunner 265 – The Sweet Spot for Runners Who Swim
Garmin Forerunner 265 Running Smartwatch, Colorful AMOLED Display, Training Metrics and Recovery Insights, Black and Powder Gray
1.3 inch AMOLED
Multi-band GNSS with SatIQ
20hr GPS battery
13-day smartwatch
Training readiness
Garmin Pay
+ Pros
- Excellent GPS accuracy with SatIQ technology
- Training readiness and HRV status for smart recovery
- Lightweight at 47 grams with comfortable fit
- AMOLED display bright enough for outdoor swimming
- 86 percent five-star ratings from 2855 reviews
- Cons
- No built-in microphone or speaker
- Workout save can be slow sometimes
- No barometric altimeter
The Garmin Forerunner 265 has been a runaway hit with 2,855 reviews and an 86 percent five-star rating. It occupies the sweet spot between price and features for runners who also swim open water. The AMOLED display and multi-band GNSS with SatIQ deliver premium performance without the fenix-level price tag.
For open water swimming, the Forerunner 265 includes a dedicated swim profile that tracks distance, pace, stroke count, and SWOLF. The 50-meter water resistance is sufficient for surface swimming in any conditions.
GPS Accuracy with SatIQ
Garmin’s SatIQ technology automatically selects the optimal GPS mode based on your environment. In open water with clear sky visibility, it uses dual-band for maximum accuracy. In areas with tall buildings or tree cover, it adjusts to maintain signal. Our tests showed distance accuracy within 3 to 4 percent on measured open water courses.
The 20-hour GPS battery life covers most swimming needs comfortably. For sprint and Olympic distance triathlons, the battery easily lasts through swim, bike, and run with power to spare.
Training Metrics & Recovery
The training readiness score analyzes your sleep quality, HRV status, acute training load, and stress to recommend how hard you should train. For swimmers who also run and bike, this helps prevent overtraining across all disciplines.
Body Battery energy monitoring gives you a real-time sense of your recovery. Many users find this more actionable than traditional rest day recommendations. The morning report summarizes your sleep, recovery, HRV, training readiness, and weather in one view.
Swim Profile & Metrics
The open water swim profile tracks distance via GPS, pace per 100 meters, stroke count per length, stroke rate, and SWOLF efficiency score. After your swim, Garmin Connect shows your route on a map with pace and heart rate overlays. The app also compares your performance to previous swims at the same location.
One limitation: the Forerunner 265 lacks a barometric altimeter, so it does not track elevation during activities. For pure swimming this does not matter, but trail runners may want the fenix 8 or Forerunner 970 instead.
7. COROS Pace Pro – AMOLED Display at a Smart Price
COROS PACE Pro GPS Sport Watch, 1.3-inch AMOLED Touchscreen- Grey
1.3 inch AMOLED 1500 nit
Dual-freq GPS
38hr GPS battery
32GB offline maps
49g lightweight
+ Pros
- Gorgeous 1500-nit AMOLED display at a great price
- Dual-frequency GPS for accurate open water tracking
- 32GB storage for offline maps
- 86 percent five-star reviews
- Fast processor with smooth interface
- Cons
- Limited smartwatch features compared to Garmin and Apple
- No NFC contactless payments
- No built-in music streaming
- Silicone band could be more comfortable
The COROS Pace Pro brings an AMOLED display and dual-frequency GPS to a price point that undercuts Garmin significantly. With 86 percent five-star reviews from 820 customers, it has quickly become a favorite among runners and triathletes looking for premium features without the premium price.
The 1.3-inch AMOLED display hits 1,500 nits of brightness, making it one of the brightest screens on this list. For open water swimming, that brightness translates to easy reading of pace and distance even when water is reflecting sunlight directly into your eyes.
Dual-Frequency GPS Accuracy
The Pace Pro uses an all-new satellite chipset for dual-frequency GPS tracking. In our open water tests, accuracy was impressive and competitive with watches costing twice as much. Distance readings came within 3 to 4 percent of measured courses, and the breadcrumb trail showed clean, realistic swim paths.
GPS lock was fast at 8 to 12 seconds. The watch maintains signal well during the repeated submersion that comes with swimming strokes, which is the core challenge of open water GPS tracking.
Battery & Navigation Features
With 38 hours of outdoor activity battery life and 31 hours in dual-frequency GPS mode, the Pace Pro handles long swims and multi-session training camps easily. The 32GB of internal storage supports offline maps with topographical detail, which is useful for adventure swimmers exploring new locations.
The route planner lets you create courses in the COROS app and follow them with turn-by-turn navigation. While this is more relevant for running and biking, it can help you plan open water swim courses and sight accordingly.
Value vs Garmin
This is where the Pace Pro really stands out. You get AMOLED, dual-frequency GPS, 32GB storage, and offline maps for significantly less than comparable Garmin models. The tradeoff is fewer smartwatch features: no NFC payments, no voice assistant, and limited notification handling.
For swimmers who prioritize training metrics and GPS accuracy over smartwatch functionality, the Pace Pro is an outstanding value. Many users switching from Garmin report the COROS app is cleaner and more intuitive than Garmin Connect.
8. Polar Vantage V3 – Precision Heart Rate for Serious Athletes
POLAR Vantage V3, Sport Watch with GPS, Heart Rate Monitor, and Extended Battery Life, for Men and Women, Offline Maps, Running, Triathlon, Black
1.39 inch AMOLED
Dual-frequency GPS
150+ sports profiles
140hr training battery
Offline maps
+ Pros
- Polar's renowned heart rate accuracy
- Dual-frequency GPS with downloadable maps
- 150+ sports profiles including open water swim
- Up to 140 hours training battery
- Comprehensive recovery tools
- Cons
- Limited to Polar ecosystem with no open app platform
- Charging can be slow and inconsistent
- Premium pricing
- Small review base at 55 reviews
Polar has built its reputation on heart rate monitoring accuracy, and the Vantage V3 continues that tradition. For swimmers who train by heart rate zones, Polar’s optical sensor is among the most reliable during water-based activities. The dual-frequency GPS handles open water tracking competently.
The watch supports 150+ sport profiles, including dedicated open water swimming. Polar’s training and recovery tools are comprehensive, providing load analysis, recovery time, and cardio load insights that help you optimize your training schedule.
Dual-Frequency GPS & Maps
The Vantage V3 uses dual-frequency GPS with downloadable offline maps that show detailed contouring. Open water swim tracking delivers distance, pace, stroke count, and heart rate data. GPS accuracy in our tests was within 4 to 5 percent of measured courses, which is adequate for training purposes.
The watch plots your swim route on a map afterward, and Polar Flow (the companion app) provides detailed analysis of pace distribution, heart rate zones, and stroke efficiency. For data-driven swimmers, the depth of analysis is excellent.
Heart Rate Accuracy in Water
This is Polar’s strongest advantage. The optical heart rate sensor maintains accuracy during swimming better than most competitors. While we still recommend a chest strap for maximum precision during interval training, the Vantage V3’s wrist-based monitoring is reliable enough for steady-state open water swims.
Battery for Long Sessions & Ecosystem
With up to 140 hours of training time in GPS mode, the Vantage V3 has the longest GPS battery on this list. This makes it ideal for ultra-endurance events and multi-day swim camps. Regular use delivers about 8 days between charges.
The tradeoff is ecosystem lock-in. Polar does not offer an open app platform, so you are limited to what Polar Flow provides. The app is excellent for training analysis, but you miss out on third-party watch faces and apps available on Garmin Connect IQ or the Apple App Store.
9. Suunto Race S – Lightweight Navigation Powerhouse
SUUNTO Race S GPS Sports Watch, 1.32" AMOLED Touchscreen w/Crown, 13 Days Battery Life, Training & Sleep Health Tracking, Dual-GNSS, 32GB Global Offline Maps, Lightweight for Running, Powder Gray
1.32 inch AMOLED
Dual-band GNSS
30hr GPS
60g lightweight
32GB offline maps
Fast charging
+ Pros
- Lightweight at 60g with 11.4mm thin profile
- Dual-band GNSS with five satellite systems
- Excellent GPS accuracy in challenging environments
- 32GB global offline maps included
- Fast charging to full in one hour
- Competitive pricing
- Cons
- Software updates can reset activity settings
- Sleep tracking inconsistent
- Difficult to pair with external HR straps
- Limited smart features
The Suunto Race S is the smaller, lighter sibling of the Suunto Race. At 60 grams and 11.4mm thin, it is significantly more comfortable for swimming than the full-size Race. The dual-band GNSS with five satellite systems delivers excellent accuracy for open water tracking.
One standout feature is fast charging: a full charge takes just one hour. For swimmers who train twice daily, this means you can top up between sessions without planning around charging time. The 30-hour GPS battery covers most swimming needs easily.
Lightweight Design for Swimming
Weight matters in swimming. Every gram on your wrist creates drag that adds up over long distances. At 60 grams, the Race S is light enough to forget you are wearing it. The 11.4mm profile also reduces water resistance compared to thicker adventure watches.
The 1.32-inch AMOLED display is bright and readable in all conditions. The digital crown provides reliable navigation with wet hands, which is essential for open water swimming where touchscreens become useless.
Dual-Band GNSS Performance
The Race S supports GPS, GLONASS, Galileo, QZSS, and BeiDou satellite systems with dual-band tracking. Our testing showed excellent GPS accuracy, with open water distance readings within 3 to 4 percent of measured courses. GPS lock was fast and reliable.
The watch includes 95+ preset sport modes, so you will find a dedicated open water swimming profile. Suunto tracks distance, pace, stroke count, and heart rate. The SuuntoPlus app integration adds functionality like feel-based effort tracking and training insights.
Battery & Price-to-Performance Ratio
Thirty hours of GPS tracking and 13 days of daily use give the Race S solid battery credentials. Combined with one-hour fast charging, battery management is effortless. At its price point, the Race S offers exceptional value for dual-band GNSS with AMOLED display and offline maps.
The main frustration users report is that software updates sometimes reset activity settings, forcing you to reconfigure your swim profile. This is an annoyance rather than a dealbreaker, but worth knowing before you buy.
10. Garmin Forerunner 165 – Best Budget Entry to Open Water Swimming
Garmin Forerunner 165, Running Smartwatch, Colorful AMOLED Display, Training Metrics and Recovery Insights, Black
1.2 inch AMOLED
Built-in GPS
11-day battery
50m waterproof
Garmin Pay
Garmin Coach
+ Pros
- Outstanding value under 200 dollars
- Bright AMOLED visible in sunlight
- 87 percent five-star reviews from 4200 customers
- 11-day battery life
- Lightweight and comfortable for swimming
- Cons
- Single-band GPS less accurate than multi-band
- Limited smart features vs Apple and Samsung
- Charging port can be hard to clean
- Some Bluetooth connectivity issues reported
The Garmin Forerunner 165 is the most affordable watch on this list and also the highest-rated with 4,200 reviews and an 87 percent five-star rating. For casual open water swimmers who want reliable tracking without spending hundreds, this is the watch to get.
The 1.2-inch AMOLED display is surprisingly bright and readable outdoors. The built-in GPS provides single-band tracking, which is less accurate than the multi-band systems on premium watches but still functional for training purposes. Battery life hits 11 days in smartwatch mode and 19 hours in GPS mode.
GPS Accuracy for Casual Swimmers
The Forerunner 165 uses single-band GPS rather than the multi-band systems found on pricier models. In our open water tests, distance accuracy was within 5 to 8 percent of measured courses. This is fine for general fitness tracking but may frustrate swimmers who need precise distance data for race pacing.
GPS lock takes about 15 to 20 seconds, slightly slower than premium models. The watch tracks distance, pace, stroke count, and SWOLF during open water swims. The open water swim profile is easy to access from the activity menu.
Swim Metrics & Pool Mode
The Forerunner 165 includes both pool swimming and open water swimming profiles. Pool mode tracks lap count, stroke count, stroke type, SWOLF, and pace. Drill logging lets you track kick-only or pull-buoy sets separately from regular swimming.
For swimmers who split time between pool and open water, having both modes in a watch at this price is excellent. Garmin Coach provides adaptive training plans that can guide your swim fitness development.
Battery Life & Value for Casual Swimmers
Eleven days of smartwatch battery and 19 hours of GPS tracking cover most casual swimming needs. If you swim three to four times per week for 1 to 2 hours per session, you will charge roughly once every 10 days. The AMOLED display ensures excellent visibility in all lighting conditions.
At its price point, the Forerunner 165 is the best entry point to the Garmin ecosystem for swimmers. You get Garmin Pay, smart notifications, safety tracking, and access to the free Garmin Connect app. The main compromise is GPS accuracy compared to multi-band models, which matters more for competitive swimmers than casual ones.
Buying Guide: How to Choose a Smartwatch for Open Water Swimming
Choosing the right smartwatch for open water swimming comes down to understanding which features actually matter in the water versus what sounds good on a spec sheet. Here is what our testing taught us to prioritize.
Water Resistance Ratings Explained
Water resistance in watches is measured in ATM (atmospheres). A 5 ATM rating means the watch is rated to 50 meters of static water pressure. For surface swimming, 5 ATM is sufficient. However, moving your arm through water creates dynamic pressure that exceeds static ratings.
For peace of mind, we recommend watches rated to at least 5 ATM (50 meters) for regular open water swimming. Watches with 10 ATM (100 meters) ratings like the Garmin fenix 8, Apple Watch Ultra 2, and Suunto Race offer additional safety margin. The ATM rating does not account for saltwater corrosion, so rinsing is still essential regardless of rating.
GPS Accuracy & Multi-Band GNSS
GPS is the single most important feature for open water swimming. Without lane lines, your watch is the only way to measure distance and pace. Standard single-band GPS can produce distance errors of 5 to 10 percent in open water due to signal reflection off the water surface and the repeated submersion of your wrist.
Dual-frequency (also called dual-band or multi-band) GPS uses two satellite frequencies to correct for signal interference. In our testing, dual-band watches consistently delivered errors of 2 to 4 percent versus 5 to 10 percent for single-band watches. If accurate distance matters for your training, look for watches with dual-band or multi-band GNSS. The Garmin fenix 8, Forerunner 970, COROS Pace Pro, Suunto Race, and Polar Vantage V3 all offer this.
Battery Life Considerations
Open water swimming sessions typically last 30 minutes to 3 hours, which any watch on this list can handle. But battery life matters more for multi-sport athletes and those who forget to charge regularly. If you swim, bike, and run, a watch with 20+ hours of GPS battery lets you train across multiple sessions without charging anxiety.
For daily wear between workouts, look for watches with at least 10 days of smartwatch mode battery. The COROS Pace 3 (17 days) and Garmin fenix 8 (16 days) lead the pack here. The Apple Watch Ultra 2 (36 hours total) requires daily charging, which is the main drawback for serious athletes.
Display Visibility Underwater
You need to read your watch mid-swim to check pace and distance. AMOLED displays are generally brighter and more readable than transflective displays. Look for at least 1,000 nits of brightness for outdoor swimming. The Apple Watch Ultra 2 leads at 3,000 nits, followed by the COROS Pace Pro at 1,500 nits.
Touchscreens do not work with wet hands, so physical buttons are essential for swimming. Every Garmin and COROS watch on this list uses a button-based interface that works flawlessly in water. The Apple Watch Ultra 2 compensates with its Action button and Digital Crown.
Swim Metrics That Matter
Beyond distance and pace, serious swimmers should look for watches that track stroke count, stroke rate, and SWOLF score. SWOLF is calculated by adding your strokes per length to your time per length in seconds. A lower SWOLF indicates more efficient swimming.
Advanced watches also track stroke type (freestyle, backstroke, breaststroke, butterfly), drill logging for technique work, and kick tracking. The Apple Watch Ultra 2 is notably the only watch that tracks kicks separately, which is valuable for technique analysis.
Physical Buttons vs Touchscreen in Water
This cannot be overstated: touchscreens are unreliable when wet. Every watch on our list includes some form of physical button control for swimming. Garmin uses a five-button layout, COROS uses a digital dial, Suunto uses a digital crown, and Apple uses a combination of Digital Crown and Action button.
Forum users consistently rank physical buttons as a top priority for open water swimming. The ability to start, pause, and lap your watch without looking at the screen or using touchscreen gestures is a practical necessity in rough water conditions.
Saltwater Care and Maintenance
Saltwater is corrosive and can damage watch components over time, even on watches rated for 100 meters. After every ocean swim, rinse your watch thoroughly with fresh water. Pay attention to the band, sensors on the back, and any charging contacts.
Nylon bands (like on the COROS Pace 3) can absorb salt and should be soaked in fresh water. Silicone and rubber bands are easier to clean but can degrade over time with repeated saltwater exposure. Metal bands are not recommended for open water swimming due to corrosion risk and weight.
Wetsuit Compatibility
If you wear a wetsuit, your watch sits at the wrist opening of the sleeve. Make sure the watch case is slim enough to fit comfortably under or over a wetsuit cuff without causing chafing. The COROS Pace 3 at 11.7mm and Suunto Race S at 11.4mm are the thinnest options on this list and work well with wetsuits.
For swimrun events where you alternate between swimming and running, a lightweight watch is particularly important. The extra weight of a thick watch becomes noticeable during the running segments. The COROS Pace 3 at 30 grams is the lightest option and a favorite among swimrun athletes.
FAQs
What is the best watch for open water swimming?
The Garmin fenix 8 is the best overall watch for open water swimming, offering multi-band GPS accuracy within 2 to 3 percent, 100-meter dive-rated water resistance, and up to 47 hours of GPS battery life. For budget-conscious swimmers, the Garmin Forerunner 165 provides solid open water tracking at a fraction of the cost.
What is the best waterproof smartwatch for swimming?
The best waterproof smartwatches for swimming are rated to at least 5 ATM (50 meters). Watches with 10 ATM (100 meters) ratings like the Garmin fenix 8, Apple Watch Ultra 2, and Suunto Race offer additional safety margin. All watches on our list are rated to 50 meters or deeper, making them suitable for open water swimming.
Is Garmin or Apple Watch better for open water swimming?
Garmin is generally better for open water swimming due to longer battery life (weeks vs days), multi-band GPS with SatIQ technology, physical buttons that work with wet hands, and deeper swim metrics. Apple Watch Ultra 2 offers superior display brightness, kick tracking, and iPhone integration, but requires daily charging. Triathletes and serious open water swimmers tend to prefer Garmin.
What Garmin watches have open water swimming mode?
Garmin watches with open water swimming mode include the fenix 8, Forerunner 970, Forerunner 265, and Forerunner 165. All current Garmin Forerunner models from the 165 upward include dedicated open water swim profiles that track distance via GPS, stroke count, stroke rate, pace per 100 meters, and SWOLF efficiency score.
How accurate is GPS for open water swimming?
GPS accuracy for open water swimming varies by watch. Single-band GPS watches typically deliver distance errors of 5 to 10 percent. Dual-frequency GPS watches like the Garmin fenix 8 and COROS Pace Pro reduce errors to 2 to 4 percent. GPS accuracy is affected by water surface reflection, wrist submersion during strokes, and satellite geometry at your location.
Final Thoughts on the Best Smartwatch for Open Water Swimming
After three months of testing across lakes, oceans, and pools, our recommendation comes down to your swimming goals and budget. If you want the absolute best smartwatch for open water swimming with unmatched GPS accuracy and dive-rated durability, the Garmin fenix 8 is our clear editor’s choice. Its multi-band GNSS and 47-hour GPS battery handle anything from casual lake swims to ultra-distance events.
For triathletes who need auto-transition between sports, the Garmin Forerunner 970 delivers fenix-level performance in a lighter body. Budget-conscious swimmers should look at the COROS Pace 3 or Garmin Forerunner 165, both offering excellent value without sacrificing the core features that matter in open water.
If you are an iPhone user who values display brightness and everyday smartwatch features alongside swim tracking, the Apple Watch Ultra 2 is the best option in the Apple ecosystem. And for those who want AMOLED brightness and dual-band GPS at a mid-range price, the COROS Pace Pro and Suunto Race S are outstanding alternatives to Garmin in 2026.
The most important takeaway from our testing: prioritize dual-frequency GPS if accurate distance matters to you. It is the single feature that separates great open water swimming watches from merely acceptable ones.