One of the best health features of Samsung's Galaxy Watch 4 is its ability to track users' blood pressure, but unfortunately, it's something buyers in the U.S. still don't (officially) have access to. A big selling point of the Galaxy Watch 4 is blood pressure tracking. Galaxy Watch 4 users can quickly check their blood pressure at any time with the Samsung Health Monitor app — something the Apple Watch isn't even capable of.

Unfortunately, that blood pressure tracking is only available in select markets — and the United States isn't one of them. Samsung says as much in a press release, noting that, "The blood pressure feature is only available in select markets, not available in the U.S.," with no further explanation given. This is also an issue with the latest Galaxy Watch 5, and older models including the Galaxy Watch 3 and Galaxy Watch Active 2. All these smartwatches support blood pressure tracking in other countries, but in the United States, it doesn't work.

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Why Blood Pressure Tracking Doesn't Work In The U.S.

Samsung Galaxy Watch 4 Pink With Gleam

The reason for the missing functionality? U.S. government regulations. In order for a smartwatch to offer blood pressure tracking in the United States, it must first be approved by the U.S. Food and Drug Administration (better known as the FDA). That FDA approval wasn't ready when the Galaxy Watch 4 launched, and as such, it doesn't have the blood pressure feature in the U.S. even though it's present in other countries. It's undoubtedly frustrating, but it's something every smartwatch has to go through.

That then begs an important question: when will the Galaxy Watch 4 be able to offer blood pressure tracking in the U.S.? That's honestly difficult to say. Galaxy Watches have technically been capable of it for a couple of years now. Even so, the FDA doesn't seem in a rush to approve it any time soon. And it may remain that way for a while to come. There's already concern over how accurate smartwatches are for heart rate and ECG tracking. Trying to accurately measure blood pressure is even more difficult, and as such, it's something the FDA is taking its time with. Because of all this, Samsung Galaxy Watch 4 owners can only sit around and wait for the FDA to (eventually) make a decision about the blood pressure feature.

How To Enable Blood Pressure Monitoring In The U.S.

Galaxy Watch 4 Blood Pressure Monitor

While Galaxy Watch 4 users in Canada received blood pressure monitoring on their devices via an update, those in the U.S. can enable the feature using a workaround. The slightly complicated process involves installing a modded version of the Samsung Health Monitor app on both the Galaxy Watch 4 and the paired smartphone, which has been detailed by the folks over at XDA Developers. This method not only enables blood pressure monitoring in unsupported regions (not just the U.S.), but also lets users set it up with a non-Samsung phone. For reference, blood pressure monitoring is officially supported only on Galaxy smartphones running Android 7.0 and above.

Once you've followed the steps in the link above and installed the modded app on your watch and phone, you'll need to calibrate the Galaxy Watch 4's readings using a medical-grade blood pressure monitor and cuff. This means you'll either need to buy one separately, or use one in a doctor's clinic. Calibration needs to be repeated three times within three days, and Samsung recommends repeating calibration every four weeks to ensure precise measurements. Clearly, keeping the blood pressure monitor readings accurate will require long-term access to a medical blood pressure monitor, which might be more effort than it's worth for the average Galaxy Watch 4 user.

Are Galaxy Watch 4 Blood Pressure Readings Accurate?

Galaxy Watch 4 blood pressure sensors

Having blood pressure monitoring on the Galaxy Watch 4 is a convenient feature, but as far as accuracy is concerned, it doesn't compare to a medical-grade monitor. The accuracy of the blood pressure monitor depends on frequent calibration with a blood pressure monitor. If a user doesn't calibrate their smartwatch regularly, the results aren't going to be accurate.

A post by a Watch 4 user on Samsung Community suggests that even after calibration, the smartwatch only provides accurate results for a short period. Other users claim that the blood pressure readings remain close to what was measured when the smartwatch was last calibrated, with fluctuations in pressure not being detected accurately. In conclusion, the sensors on the Galaxy Watch 4 don't compare to a medical device, and shouldn't be used as a replacement for those who need to regularly monitor their blood pressure for health reasons.

Source: Samsung 1, 2, XDA Developers