Youth national teams In 2011, Swanson attended the annual United States under–14 girl's national team identification camp from July 13 to August 7 in Portland, Oregon. The camp was used as an evaluation for U–14 training camp held in September. Swanson was then called into the U–14 national team training camp at
Home Depot Center in
Carson, California, from September 18 to 25. In 2012, Swanson attended a U–15 national team training camp from February 11 to 18. She then joined the team for a second training camp from June 3 to 10 at The Home Depot Center. Also during the summer, the U–14 national team conducted three separate training camps to replace the large identification camp of previous years. Swanson attended the second camp, which ran from August 12 to 19.
U-17 WNT In 2013, Swanson attended a U–15 national team training camp from February 24 to March 2 at the
Olympic Training Center in
Chula Vista, California. She then moved up to the
U–17 national team and traveled to San José, Costa Rica for an international tournament in late April. Following the tournament, Swanson joined the U–17 team for a training camp from June 9 to 16. In preparation for the
2013 CONCACAF Women's U–17 Championship, Swanson attended another U–17 training camp from July 21 to 31 in
Columbus, Ohio, as well as a camp in Lakewood Ranch, Florida, from September 15 to 22. In late September 2013, Swanson was named to the roster for the 2013 CONCACAF U–17 Women's Championship held in
Jamaica from October 30 to November 9. Before heading to Jamaica, the team trained together once again in Lakewood Ranch for seven days. During the tournament, Swanson was a key player and leading scorer with five goals and three assists. In the semifinal match against Mexico on November 7, the United States fell in penalties after a 1–1 tie in regulation. With a third-place finish in the tournament, the United States did not qualify to the
2014 FIFA U–17 Women's World Cup. Swanson remained with the U–17 national team for a short time in 2014. She started off the year with the team at a training camp from January 11 to 19 in Carson, California. The camp served as a preparation for an international tournament held in February. Swanson was on the roster for the tournament, which was held at the U.S. National Team Training Center in Carson. In their final match of the tournament on February 9, the United States faced Japan. During the game, Swanson scored her fourth goal of the tournament to help the United States pull away the 2–1 victory and win the tournament title.
U-20 WNT At the end of her time with the U–17 national team, Swanson was called up to the
U–20 national team for a training camp from February 22 to March 2 that also featured a match against China. Swanson was then on a 25–player roster for a U–20 training camp from April 13 to 20. In preparation for the 2014 FIFA U–20 Women's World Cup in August, the U–20 team also trained in May and July, with a trip to Europe in June. After the team's final camp from July 9 to 23, Swanson was named to the roster for the 2014 FIFA U–20 Women's World Cup. At 16, she was the youngest member of the team. Swanson played all 90 minutes of the team's first match of the tournament against Germany on August 5. In the team's second group match against Brazil on August 8, Swanson suffered a right ankle injury in the 27th minute and was replaced by Taylor Racioppi. Despite the injury, Swanson went on to start the remaining two matches of the tournament. Swanson started off 2015 at a U–20 national team training camp in
Sanford, Florida, from January 24 to 31. The training camp featured a match against German club
Bayern Munich. Swanson started in that match; however, the U–20 team was defeated 4–0. Following the training camp, Swanson was named to the 22–player roster for an invitational tournament in La Manga, Spain. In the first match of the tournament, Swanson scored both goals of the game to help the United States defeat Norway. Swanson wore the captain's armband during the team's second match against the Netherlands on March 7. Swanson played all 90 minutes in the team's last match against Sweden on March 9. In November 2015, Swanson was named to the roster for the
2015 CONCACAF Women's U–20 Championship in December. Swanson was the most experienced player on the roster and also captained the team. In the first match against Mexico on December 4, Swanson scored on a penalty kick in the 20th minute. The United States qualified for the
2016 FIFA U-20 Women's World Cup after defeating Honduras in the semifinal on December 11. Swanson helped the team win the tournament with a 1–0 win over Canada on December 13. Following the tournament, Swanson was awarded the Golden Boot for most goals scored and the Golden Ball for best player of the tournament. On December 18, Swanson was named the
2015 U.S. Soccer Young Female Player of the Year. Despite being a member of the senior national team in 2016, Swanson at age 18 was still comfortably age eligible for the
2016 FIFA U-20 Women's World Cup. After returning from the Olympics, Swanson joined the U-20 team at a training camp on September 1, 2016. Swanson captained the U-20 United States team at the
2016 FIFA U-20 Women's World Cup where she was the most experienced player on their team with 23 international matches and 17 goals. In the second group stage game against New Zealand the United States won 3–1, Swanson scoring and receiving player of the match honors. By participating in the
2016 FIFA U-20 Women's World Cup and the
2016 Summer Olympics, Swanson made history by being the first United States women's player to play in both tournaments in the same year. Swanson would still be age eligible for the
2018 FIFA U-20 Women's World Cup.
Senior national team 2016 Following a successful run with the U-20 women's national team, Swanson was called up to the senior national team for the first training camp of 2016 from January 5 to 21 leading up to a match against Ireland. At age 17, she was one of the youngest field players to be called up to the team in 15 years. On January 23, 2016, Swanson earned her first cap for the
USWNT during the match against
Ireland, coming in for Alex Morgan in the 58th minute. She was the youngest player to debut for the national team since
Heather O'Reilly's debut in 2002. She then became the 19th United States player to score in her debut when she scored her first international goal in the 83rd minute to secure the United States' 5–0 win. Following her first appearance, Swanson was named to the 20–player roster for
2016 CONCACAF Women's Olympic Qualifying and became the youngest player to be named to an Olympic qualifying roster for the USWNT. In the team's opening match against
Costa Rica on February 10, Swanson replaced
Crystal Dunn in the 68th minute. She made her third appearance for the team in their second match of the tournament, coming in for
Ali Krieger in the 75th minute to help the USWNT defeat
Mexico 1–0. Swanson made her first start in the team's match against
Puerto Rico on February 15. During the match, she recorded an assist in the 6th minute. In the 18th minute, Puerto Rico player Selimar Pagan took down Swanson in the penalty box and the USWNT was given a penalty kick, which
Carli Lloyd scored. In the 60th minute, Swanson sent a cross towards
Alex Morgan, but it was deflected off Puerto Rican defender Ashley Rivera and into her own net. Swanson started in the semifinal match against
Trinidad and Tobago on February 19, helping the USWNT qualify to the
2016 Olympic Games in
Rio de Janeiro after a 5–0 victory. Swanson also made the start in the final against
Canada, helping the USWNT win the tournament after defeating Canada 2–0. Swanson was named to the roster for the
2016 SheBelieves Cup that took place from March 3 to 9. She started in the team's opening match of the tournament on March 3 against
England. In the match against
France on March 6, Swanson assisted the only goal of the match in stoppage time, giving the USWNT the win. She also made an appearance in the final match of the tournament against
Germany and the USWNT won the 2016 SheBelieves Cup with a 2–1 win. Swanson joined a 23–player roster for a training camp ahead of two matches against
Colombia in early April. On April 6, Swanson scored her second international goal off an assist by Carli Lloyd in the team's first match against Colombia. She then assisted Lloyd's goal six minutes later. She played all 90 minutes in the second match against Colombia on April 10. When Swanson turned 18 on April 29, 2016, she had added her name to a list of records, including fifth all-time for most USWNT caps before the age of 18 with 11, third for most goals before the age of 18 with two, fourth in most starts before the age of 18 with seven, and first for most assists before the age of 18 with five. Swanson was on the roster for a short training camp ahead of another two–game series against Japan in early June. She played all 90 minutes of the first match on June 2 in
Commerce City, Colorado, and made an assist in the 27th minute. Swanson did not dress for the second match on June 5 due to illness.
2016 Summer Olympics On July 12, 2016, Swanson was named to the 18–player team that would represent the United States at the
2016 Olympic Games in
Rio de Janeiro. She made her Olympic debut on August 3 in the team's opening group match against
New Zealand. On August 9, Swanson came in for
Megan Rapinoe in the 33rd minute of the team's final group match against
Colombia. She scored in the 59th minute, becoming the youngest United States player to score a goal in the Olympics. She put the United States ahead 2–1 with her goal; however, the match ended in a 2–2 draw. In the quarterfinals, Swanson started in the match against
Sweden on August 12. The game was tied 1–1 after regulation time and Swanson was replaced by
Lindsey Horan in the 114th minute in extra time. The United States were then defeated by Sweden in penalty kicks.
2017 Across the 16 games played by the USWNT in 2017, Swanson played in 12 and started in 9 of them. She was named to the roster for the
2017 SheBelieves Cup. After turning 19 on April 29, 2017, Swanson's records for the USWNT were tied with
Mia Hamm for third in USWNT history for goals before age of 19 with four, fourth in caps with 22, and second in starts with 15.
2018 Swanson started 2018 off strong with her first career brace on January 21, 2018, against
Denmark, the USWNT winning the game 5–1. In her last game as a teenager on April 8, 2018, against
Mexico she scored her fifth goal of the calendar year. For her teenage national team stats, Swanson was second all-time in starts before the age of 20 with 27, second all-time in caps before the age of 20 with 35, tied third all-time in goals before the age of 20 with 11, and first all-time in assists before the age of 20 with 12. She made her comeback on August 31, 2018, in a game against Chile. The United States won 3–0, Swanson assisting the third goal scored by
Christen Press who was being honored that game for 100 national team caps.
2019 Swanson scored the first goal of the year for the United States in a 3–1 loss against
France played at
Le Havre. She played in the
2019 SheBelieves Cup where the United States finished as runners up. On April 4, Swanson scored her second career brace in a match against
Australia, the United States winning 5–3. Her first goal in that game came just 37 seconds after she had subbed onto the pitch in the 67th minute. Swanson also scored against
Mexico in the final send off series game for the United States before the
2019 FIFA Women's World Cup.
2019 FIFA Women's World Cup Swanson was one of 23 players called up for the
2019 FIFA Women's World Cup. At 21 she was the second youngest player on the roster behind 20 year old
Tierna Davidson. The USWNT played their first game on June 11, 2019, against
Thailand, winning by a historic 13–0 margin. Swanson subbed on in the 69th minute, assisting
Megan Rapinoe's goal in the 74th minute and later scoring her first
FIFA Women's World Cup goal in the 85th minute. She was 21 years and 43 days old when she scored, making her the third youngest USWNT player in history to score at the
FIFA Women's World Cup. She appeared in all three group stage games against
Thailand,
Chile and
Sweden. The USWNT went on to win the
2019 FIFA Women's World Cup.
2020 Swanson was named to the roster for the
2020 SheBelieves Cup, marking her fifth appearance at the tournament. In their third and final game of the tournament against
Japan, the United States won 3–1, Swanson assisting a goal scored by
Lindsey Horan. After the USWNT had a break in international playing due to
COVID-19, Swanson was unavailable to participate in the national team camp being held from October 18–28, 2020 due to injury.
2021 Swanson began the year attending the annual January camp for the United States. However, injury and inconsistent play meant she did not see the field for the United States until later that year, in a series of friendlies in September and October versus
Paraguay and the
South Korean national team. Swanson's return to play was strong, notching three assists in the first game against Paraguay, the most for any United States player in one game since
Alex Morgan in the
2019 FIFA Women's World Cup.
2022 Swanson saw a return to normalcy in 2022, playing in 15 of the United States' 18 games and starting 13 of them. She was named to the roster for the United States in the
2022 SheBelieves Cup and finished as the leading goal scorer of the tournament, hitting the back of the net once versus
New Zealand and twice versus
Iceland. As the year went on, Swanson continued to break records, both those of the United States' and her own. Her goal against Uzbekistan on April 12 marked a four-match scoring streak, overtaking the record from 2021 previously held by
Megan Rapinoe. During the
2022 CONCACAF W Championship, Swanson played in her 75th national team cap for the United States, the 49th player to do so and the youngest since
Heather O'Reilly in 2008. She had 14 goal involvements, 7 goals and a team-high 7 assists – her career best.
2023 Swanson continued her strong form in early 2023, scoring three times in a pair of friendly games against New Zealand and another three times at the
2023 SheBelieves Cup. This meant she scored in five consecutive USWNT games, a personal best. On April 9, 2023, the
United States Soccer Federation confirmed that during a USWNT friendly against
Ireland on April 8, Swanson tore her left
patella tendon.
2024 Following her recovery, Swanson returned to the USWNT for the
2024 SheBelieves Cup in April 2024. On June 1, scored a brace against
South Korea in a friendly match in her home state of Colorado. On June 26, 2024, Swanson was selected to the 18-player roster for the
2024 Summer Olympics in France, marking her second Olympic tournament. In the group stage, she scored a brace in the 3–0 win against
Zambia and added another goal against
Germany. In what was her 100th international appearance, she scored the 57th-minute winning goal to defeat
Brazil 1–0 in the Olympic final, earning a gold medal. ==Personal life==