The wedding ring is traditionally worn on the fourth finger of the left hand in many Western cultures, including the UK, US, France, Portugal, Switzerland, Australia, and Canada. This tradition dates back to the ancient Romans, who believed that the fourth finger on the left hand had a vein that ran directly to the heart, called the Vena Amoris, meaning vein of love. With the heart at the center of emotions, this finger was thought to be the best finger to wear an engagement or wedding ring on. However, there are no laws surrounding which finger to wear a wedding ring on, and the ring finger is most commonly recognized as the fourth finger from the thumb on the left hand.

Its worth noting that wearing an engagement ring or wedding band on the left hand is not a global tradition. In Russia, Germany, Norway, and India, engagement rings are worn on the right hand. In Switzerland, the engagement ring is typically worn on the right ring finger, and the wedding band is worn on the left.

In summary, the wedding ring is traditionally worn on the fourth finger of the left hand in many Western cultures, but there are no laws surrounding which finger to wear a wedding ring on.