The pair were married in 2001 but separated three years later in 2004. The TV and radio presenter and Dr. Who actress were 18 years apart in age.
London's High Court heard their decree nisi and it was granted. Neither partner was in court at the time.
The marriage crumbled partly due to the age difference. Piper was only 18 when they met and married in Las Vegas. Now 24, Billie is at the top of her game as the female lead in the Dr. Who series.
Evans said: "Our lives changed. She got her career back on track. It was evident we weren't the same people, and although splitting up hurt, it was the best thing we ever did, apart from marrying in the first place.
She was too young for me - only 18 when we met - but it was a real adventure."