Ifemelu, a Nigerian woman living in America, gets her hair braided at an African salon. She interacts with the women there and remembers her past. Meanwhile Obinze, a rich man living in Nigeria, emails Ifemelu and remembers his own past. The chapters are also scattered with posts from Ifemelu’s blog about race in America.
Ifemelu grows up in Lagos, Nigeria. She is close with her Aunty Uju, who becomes the mistress of The General, a wealthy married man. Ifemelu meets Obinze at school and they fall in love. Obinze introduces Ifemelu to his mother, a professor. Aunty Uju gets pregnant and has The General’s baby, named Dike. The General dies and Uju flees with Dike to America.
Ifemelu and Obinze go to university together. They start having sex and Ifemelu has a pregnancy scare. There are many strikes and the university is shut down. Ifemelu considers going to America, and she gets a visa and a scholarship to a university in Philadelphia.
When Ifemelu arrives she stays in Brooklyn for the summer with Aunty Uju and Dike. Uju seems stressed out and unhappy. She gives Ifemelu a fake identity card to find work, and Ifemelu goes to Philadelphia for school. Ginika, her friend from Nigeria, helps introduce Ifemelu to American culture and its racial politics. Ifemelu can’t find a job, and she starts using an American accent. She makes friends with some African students.
Ifemelu’s money runs out, and she accepts a job helping a tennis coach “relax.” He touches her sexually and gives her $100. Ifemelu goes home and feels guilty and depressed. She breaks off contact with Obinze, and stops eating and sleeping. Ginika finds her a job babysitting for a wealthy woman named Kimberly.
Kimberly and Ifemelu become friends. Ifemelu visits Aunty Uju who has gotten married and moved to Massachusetts, and flirts with a young man named Blaine on the trip there. Ifemelu starts dating Kimberly’s cousin Curt, a rich, handsome white man. Curt takes Ifemelu on many trips and helps her get a good job and a green card.
Meanwhile Obinze is hurt by Ifemelu’s sudden silence. He graduates and moves to England. He stays with friends but can’t find a good job, and his visa expires. He rents an identity card and finds menial work. He makes friends with a boss and coworker, but then is turned in as an illegal immigrant. Obinze borrows money from Emenike, an old friend who has gotten rich in England, and pays for a green-card marriage with a girl named Cleotilde. On the day of his wedding, though, Obinze is arrested and sent back to Nigeria.
Ifemelu, feeling the pressure of her interracial relationship, cheats on Curt and he breaks up with her. She gets depressed again. Her parents visit. Ifemelu starts her race blog and it gets very popular. She becomes well-known and is asked to give talks. She meets Blaine again and they start dating. He is a professor at Yale and very principled. Ifemelu also meets his domineering sister Shan.
Ifemelu and Blaine start following Barack Obama’s presidential candidacy. They have a fight when Ifemelu skips a protest Blaine arranges. They get back together, but are mostly united by their shared passion for Obama. Ifemelu wins a fellowship to live at Princeton. After a while she grows restless and decides to quit her blog, break up with Blaine, and move back to Nigeria.
It is a week before she plans to return to Nigeria when Ifemelu goes to the hair salon. As she leaves the hair salon, Aunty Uju calls to tell her that Dike tried to kill himself. Ifemelu rushes to be with him.
Obinze has gotten rich selling real estate. He is married to the beautiful Kosi and has a daughter.
Ifemelu spends lots of time with Dike and then goes to Lagos. Her old friend Ranyinudo helps her readjust, teasing her about being an “Americanah.” Ifemelu goes to a club for Nigerians back from living abroad. She starts working for a women’s magazine but then quits and starts a new blog about life in Lagos. Dike visits her.
Ifemelu finally calls Obinze and they meet up. They start seeing each other daily and rekindle their romance. They spend blissful weeks together, but then break up again in the face of his marriage. Obinze tries to divorce Kosi, but she won’t accept it. After seven months Obinze shows up at Ifemelu’s door, saying he is leaving Kosi and wants to try again with Ifemelu. She invites him in.