linguistic:voice_change, quality:correction
2013

Biles' senior international debut was in March at the 2013 American Cup, a FIG World Cup event. She and Katelyn Ohashi were named as replacements for Elizabeth Price and 2012 Olympic gold medalist Kyla Ross, both of whom withdrew from the competition because of injuries. Biles led for two rotations but finished second behind her teammate, Ohashi, after a fall off the beam.

Biles traveled to Jesolo, Italy, to compete at the 2013 City of Jesolo Trophy. She took the all-around, vault, balance beam, and floor exercise titles in addition to contributing to the U.S. team's gold medal. She and the U.S. delegation next competed at an international tri-meet in Chemnitz, Germany, against teams from Germany and Romania. The U.S. won the team gold medal. In addition, Biles won the vault, balance beam, and floor titles, and tied for second in the all-around, behind Kyla Ross, after a fall on the uneven bars.

In July, Biles competed at the 2013 U.S. Classic. She performed poorly, falling several times, and did not compete vault after twisting her ankle on the floor exercise. In the aftermath of this poor performance, Biles consulted a sports psychologist whom she credits with helping her anxiety and confidence issues and allowing her to begin her streak of dominance in the sport.

Biles competed at the 2013 U.S. National Gymnastics Championships in August, where she was crowned the national all-around champion. Biles also won silver in all four individual events. After the USA Gymnastics National Championships, Biles was named to the Senior National Team and was invited to the qualifying camp for the 2013 World Artistic Gymnastics Championships in Texas. She was selected for the World Championships team.

In October, Biles competed at the 2013 World Championships in Antwerp, Belgium. She qualified first in the all-around, second to the vault final, sixth to the uneven bars final, fifth to the balance beam final, and first to the floor final, making her the first American gymnast to qualify to the all-around and all four event finals since Shannon Miller in 1991. Biles competed cleanly during the women's individual all-around and won the competition with a score of 60.216, almost a point ahead of silver medalist Ross, and almost a point and a half better than the bronze medalist, 2010 world all-around champion Aliya Mustafina.

At the age of 16, Biles became the seventh American woman and the first African American to win the world all-around title. In the event finals, she won silver on the vault, behind defending world champion and Olympic silver medalist McKayla Maroney and ahead of 2008 Olympic gold medalist Hong Un Jong of North Korea; bronze on the balance beam, behind Mustafina and Ross; and gold on the floor exercise, ahead of Italy's Vanessa Ferrari and Romania's Larisa Iordache. She finished fourth in the uneven bars final, behind China's Huang Huidan, Ross, and Mustafina.