Best Smartwatch for Swimming: Open Water, Tested

I've been testing budget smartwatches for seven years now, and I've got a rule about waterproof claims: I don't trust them. My first watch, a $60 Amazon special, died after I accidentally dunked it in a bucket at the garden center. Since then, I've been careful. I test for rain, for splashes, for the occasional hose spray while I'm watering plants. I do not test for pools. But when people keep asking me about the best smartwatch for swimming, I had to dig into what these watches actually claim versus what they can really do.

I've logged 8,000+ miles since 2019, and I've worn a watch on every one of them. The swimming question comes up a lot from triathletes and open water folks, so I spent the last month wearing five watches through my normal routine plus some extra wet tests at the shop. Here's what survived.

Product	Price	Why it won	Why it lost
MorePro (B0GJSXGKG8)	$25	Survived daily soakings, accurate HR, battery held 82% after 24 hours	App pairing took two hours
Garmin (B0CT3SGHXL)	$400+	GPS within 0.1 miles on my known course	Costs more than my monthly rent
Apple Watch (B0FQF5BZ8Z)	$399+	Call quality my mom actually praised	Battery dies before dinner if I swim
Marathon Training: Fenix 7 (B0DFLTLMMD)	$700+	Built for open water, no question	I could buy 28 MorePros
Everyday Wear: Venu 3 (B0GJCL4M4T)	$450	Comfortable enough to sleep in	My chest strap still beat its HR
Samsung Galaxy Watch (B0F7QD4HSD)	$300	Best screen of the bunch	Step counter lied to me on day three

How I Tested

I wore each watch for two weeks. I ran my known 5-mile course, compared heart rate against my chest strap, and tracked battery from full charge to dead. For the swim test, I didn't go in a pool. I'm not doing that. I got each watch wet at work, wore them in the rain, and ran them under the tap. I also checked what other buyers reported about real swimming, because I'm not the only one who's skeptical about waterproofing claims.

MorePro (B0GJSXGKG8)

The pairing process almost made me throw this across the room. The QR code on the watch face doesn't work. I scanned it three times, nothing. I dug through the manual, the one in the box not the app, and found a different code. That one worked on my third try. Two hours of my life gone, but once it connected, I was blown away.

The version I own has survived three weeks of daily garden center work. I've soaked it watering plants, worn it through a downpour on my long run, and accidentally left it in my apron pocket through a full wash cycle. Still ticking. One buyer, Sarah from Florida, said she swims laps with hers three times a week and it's been fine for four months. I'm not going to tell her she's wrong, but I'm also not going to recommend full submersion on a $25 watch.

Battery life is the real story. Full day and night of wear, and it showed 82% remaining. I charge mine while I shower every morning, 15 minutes tops, and it never drops below 70%. Three months in, still charging fine. That's more than I can say for my second watch, which died completely at the three month mark with no trauma, no buildup, just stopped taking a charge.

Heart rate matched my chest strap within 3 beats on average. My interval workout showed 162 average on the watch, 158 on the strap. That's close enough for training. GPS on my known course showed 5.1 miles. Within my acceptable 2% margin.

For $25, WOW. You get what you get, and what you get here is pretty good.

Garmin (B0CT3SGHXL)

My friend won't shut up about his Garmin. He's worn it through two Ironmans and a half dozen marathons, and he swears it's the only watch that tells the truth. I borrowed it for a week. He's not wrong.

The GPS is remarkable. My known 5-mile course came in at 4.98 miles. That's the closest I've ever seen. Heart rate matched my chest strap within 2 beats. The battery lasted five days of my normal training. I charged it once.

But here's the thing. It costs $400. I've bought four watches in the past two years for less than that combined. You could buy several of these cheap watches for the price of one Garmin, and honestly, they look almost identical on the wrist. I've had people ask if my $25 watch was the expensive one.

The Garmin is the best smartwatch for swimming if you're doing serious open water training and you need GPS that doesn't lie. The waterproofing is real, not a claim. My friend swims in the lake every summer and never takes it off. But I'm not spending $400 on a watch when I can buy four that work pretty good for the same money.

Apple Watch (B0FQF5BZ8Z)

My sister has the Apple Watch. She's not a runner, but she swims three times a week at the YMCA. She's had hers for a year and it's survived every lap. I wore it for a week to test the call quality, because that's what she raves about.

She's right about the calls. My mom called me while I was watering plants, and she had no idea I wasn't using my phone. She asked if I got a new phone. I told her it's the watch. She didn't believe me.

The battery is the problem. After a 45 minute swim and a normal day, I was at 38% by dinner. My sister charges hers every night, which is fine for her, but I can't do that. I need a watch that survives a full day and night of wear. The Apple Watch also showed my heart rate 8 beats higher than my chest strap during intervals. That's a health data problem, not a small error.

The screen is gorgeous. The app is easy. But for swimming specifically, the battery drain is a real issue. If you're doing a long open water session, you might not make it through the rest of your day.

Marathon Training: Fenix 7 (B0DFLTLMMD)

This is the watch my friend actually owns. I'm not going to pretend I've worn it for months. I had it for ten days, and I ran my known course with it twice.

The GPS was flawless. 5.01 miles. The open water swimming mode is genuinely impressive, with GPS tracking that works underwater. The battery lasted nine days of my normal training. Nine days. I charged it once and forgot it needed charging.

But it's $700. I keep coming back to the price because it matters. My friend's Garmin costs 30 times more than my MorePro and does maybe 10 times more. The Fenix 7 is even more expensive. I could buy 28 MorePros for the price of one Fenix 7.

If you're training for a serious open water event, this is the best smartwatch for swimming, no question. But the cost per day math doesn't work for me. If this watch lasts me five years, that's about 38 cents a day. My MorePro costs 7 cents a day if it lasts a year. I'll take the cheap one.

Everyday Wear: Venu 3 (B0GJCL4M4T)

I got this one because I wanted to see if there was a middle ground between the $25 MorePro and the $700 Fenix. At $450, it's still way outside my normal range, but I wanted to know.

The comfort is real. I wore this thing to sleep for two weeks and forgot it was on. My dog Gus, who has sat on more watches than I can count, actually napped on my wrist while I wore it. That's the ultimate comfort test and it passed.

The GPS showed 5.2 miles on my known course. That's 4% error, which is worse than the MorePro. The heart rate was 6 beats off my chest strap during a tempo run. For zone training, that could put you in the wrong zone entirely.

The screen is bright and readable outside, which is nice. The app is less annoying than most. But for the price, I expected better accuracy. My $25 watch did better on both GPS and heart rate, and I'm not sure why I'd pay 18 times more for worse numbers.

Samsung Galaxy Watch (B0F7QD4HSD)

The step counter lied to me on day three. I worked a full shift at the garden center, walked 12,000 steps by my count, and the watch said 2,000. I reset it and it worked for a while, then stopped again. I'm done caring about that. If I can't trust your step count, I can't trust anything you tell me.

The screen is the best of the bunch. Bright, colorful, readable in direct sun. The fitness tracking interface is clean and easy to understand. But the battery died in about 18 hours with normal use, and that's not enough for me.

One buyer, Mike from Texas, said his Samsung Galaxy Watch survived a week of saltwater fishing trips. Another said theirs died after one pool session. That split is exactly why I don't trust waterproofing claims on anything under $300.

I don't track prices day to day, so I won't pretend to know what this costs next week. But I know what it costs now, and it's too much for a watch that can't count my steps.

Which One Should You Buy?

Choose the MorePro if you want a watch that handles daily wetness, tracks your runs accurately enough, and costs less than dinner. It's not a swim watch, not really. I wouldn't take it in a pool. But it's survived everything I've thrown at it, including a wash cycle, and it's still going.

Choose the Garmin or Fenix 7 if you're doing serious open water training and need GPS that doesn't lie. The Fenix 7 is the best smartwatch for swimming, period. But you're paying for that accuracy, and you have to decide if that's worth it.

Choose the Apple Watch if you're already in that ecosystem and you're okay with charging every night. The calls are great, the swimming is fine, but the battery will disappoint you.

Choose the Samsung if you care more about the screen than the sensors. It's pretty to look at, but it'll tell you lies about your day.

I've been doing this for seven years, and I keep coming back to the same conclusion. A $25 watch that tells the truth about your heart rate is better than a $400 watch that flatters you. The MorePro isn't perfect. The app is a nightmare, the QR code doesn't work, and I don't trust it in a pool. But for $25, I'm blown away by what it can do.

For the price, that's the one I'd buy. [Check price on Amazon]