Which is more accurate wrist or arm blood pressure monitor

One in nine participants (11 percent) had wrist systolic pressure readings that were lower by 5 mmHg or more than their upper arm reading. On average, wrist systolic blood pressure was 12.9 mmHg higher than systolic pressure measured in the aorta, the main artery delivering blood from the heart to the rest of the body.

Are Wrist Blood Pressure Monitors Accurate? Many studies and medical experts suggest wrist blood pressure monitors aren't accurate. In fact, the American Heart Association says wrist and finger monitors aren't recommended because they yield less reliable readings.