Macario was born inSão Luís, Maranhão, Brazil, to Ana Maria Cantanhede and José Melônio Macário.[6][2] She started playing football at the age of 4,[7] following the footsteps of her older brother, Estevão (known in the U.S. as Steve). She started playing in the academy ofFlamengo in São Luís. She remained there for less than 6 months before switching to theCruzeiro academy. At the age of 7, she moved with the family toBrasília, the capital of Brazil. In Brasília, Catarina played for theSantos academy, where she remained until she moved to the United States in December 2011. In Brazil, Catarina had always played for boys' teams and only started playing for a girls' team after arriving in the United States. In 2011, at the age of 12 and without speaking any English, Macario relocated with her father and brother toSan Diego, California, in order to pursue her dream of playing soccer. Her mother, a doctor, remained in Brazil in order to financially support the family. While playing for theSan Diego Surf as a youth player, she broke the all-time goalscoring record in theECNL with 165 goals.[8][9][10]
On February 1, 2017, Macario committed to play collegiately forStanford University. In her freshman year in 2017, she played 25 matches, scoring 17 goals and clinching 16 assists. As a result of her performance this year she won several awards, including being named "ESPNW Player of the Year",[8] "TopDrawerSoccer.com Freshman of the Year",[11] "Pac-12 Forward of the Year", and "Pac-12 Freshman of the Year".[12]
In her sophomore year in 2018, Macario scored 14 goals with 8 assists in 19 matches played. On December 11, 2018, she received theTopDrawerSoccer.com National Player of the Year Award.[13] On January 4, 2019, Macario won theMAC Hermann Trophy, awarded to the nation's top female and male players.[14][15] Additionally, she was named "espnW Player of the Year" and "Pac-12 Forward of the Year" for the second year in a row.[16][17]
In her junior year, Macario was the winner of theHonda Sports Award, given to the nation's top female collegiate soccer player.[18][19] She was also awarded the MAC Hermann Trophy a second time, becoming the sixth woman to repeat as winner since the award was established in 1988.[20][21]
On January 12, 2021,Lyon announced they signed Macario for 2.5 years.[23] She made her debut for Lyon in theDivision 1 Féminine on February 6, 2021, coming on as a substitute in the 37th minute forAmandine Henry in a 2–1 win againstMontpellier.[24] On May 21, 2022, Macario scored in theUEFA Women's Champions League final to help secure a 3–1 victory againstFC Barcelona. Macario along with Lyon teammateLindsey Horan became the fourth and fifth Americans to win the UEFA Women's Champion League.[25]
On June 9, 2023,Chelsea announced they had signed Macario on a free transfer from Lyon on a three-year deal.[26] Macario scored her first goal 6 minutes into her debut for Chelsea on March 3, 2024, during aWSL game againstLeicester City after returning from an ACL injury she got in June 2022.[27] In her second game for Chelsea, she scored for a 1–0 victory overEverton in theFA Cup three minutes after being subbed in.[28]
Macario is eligible to play internationally for Brazil and the United States. She was called to represent the United States at several youth levels. Macario stated that she intended to represent the United States at the senior level, turning down several approaches from theBrazilian Football Confederation.[8][10][29][30] She generally plays as a midfielder for the United States, althoughVlatko Andonovski has stated she could move to afalse nine role in the future.[4]
On October 8, 2020, Macario received her first call up to represent theUnited States at senior level, though she could not yet do this in games until she received clearance from FIFA.[31][32] Later the same day, she announced on Twitter that she had acquiredAmerican citizenship.[33][34][35] On January 13, 2021, U.S. Soccer announced that Macario received clearance from FIFA to represent the United States internationally.[36] On January 18, 2021, Macario debuted for the United States, coming in the half-time of a friendly match againstColombia,[37] thus becoming the first naturalized citizen ever to play for the US senior women's team.[38] In the next game, another friendly against Colombia, she started for the first time, scoring her first international goal, on January 22, 2021.[39]
On June 23, 2021, Macario was included in the United States roster for the2020 Summer Olympics where they placed 3rd, earning Macario a bronze medal.[40]
After missing the2023 FIFA Women's World Cup due to an ACL injury she obtained with Lyon in 2022, Macario made her return to the United States national team for the2024 SheBelieves Cup in April 2024.[41] On June 26, 2024, Macario was selected by her former Chelsea coachEmma Hayes to the 18-player roster for the2024 Summer Olympics in France.[42] On July 12, it was announced that Macario would be withdrawing from the Olympics due to "knee irritation", and thatLynn Williams would replace her on the roster.[43]