The 21-year-old, who was born in New York and moved to England when he was two, was eligible to play for the USA, England or Nigeria at senior level.
Balogun briefly played for the USA's Under-18 team, but he otherwise continued his development with the Young Lions of England from Under-17 to Under-21 level.
The Arsenal man, who is currently enjoying a successful season on loan at Ligue 1 club Reims, scored seven goals in 13 games for England's Under-21s, but he was never considered for a senior inauguration.
Despite his prolific scoring rate in France, Balogun was snubbed for a call-up for March's Euro 2024 qualifiers with Italy and Ukraine, as Gareth Southgate selected Harry Kane and Ivan Toney as his central attacking options.
Balogun appeared to hint at his disappointment on social media, posting a story on Instagram with the caption: "In life, go where you are appreciated".
With Callum Wilson, Ollie Watkins, Tammy Abraham and Marcus Rashford also vying for places in the England setup, Balogun applied to represent the USA at senior level, and FIFA accepted his request on Tuesday.
"My decision to represent the United States came together with my family. In the end it became a no-brainer, but for sure it's just something I wanted to do and it feels like I'm at home here," Balogun told ussoccer.com after his switch was confirmed.
"To represent the United States means a lot, more than people would know. I'm very proud and honoured to have this opportunity, and I want to give everything I have to make our team successful."
Head coach Anthony Hudson hailed the "extremely talented" striker as he prepares to welcome him into the senior setup, adding: "We are delighted that Folarin has chosen to represent the United States.
"Not only is he an extremely talented player, he's also a good man who is going to add value to our National Team both on and off the field at a time when the team is continuing to improve. It's clear that he values his U.S. roots and we can't wait for him to come in and be a part of the team."
Balogun could make his senior international debut for the USA in their CONCACAF Nations League semi-final with Mexico on June 15, as the Stars and Stripes bid to defend their title in the final against Panama or Canada three days later.
The 21-year-old - who has been with Arsenal since 2011 - has scored 19 goals in 34 Ligue 1 games during an exceptional campaign with Reims, sitting joint fifth in the race for the Golden Boot behind Habib Diallo, Jonathan David, Alexandre Lacazette and Kylian Mbappe.
Balogun is due to return to Arsenal for pre-season and remains under contract at the Emirates until 2025, but he could be on the move this summer in search of regular game time.
French champions Paris Saint-Germain are believed to be one of several clubs interested in Balogun, who has scored just two goals in 10 senior appearances for the Gunners.