How old the stars of 'Sex Education' are compared to their characters in the final season

Asa Butterfield plays one of the lead characters of "Sex Education," Otis Milburn. Otis is a shy nerd who forms a sex clinic in Moordale Secondary School after being inspired by his friends and his own sex therapist mother.

After Moordale closes down, Otis spends season four trying to form a new clinic at his new school, Cavendish College. According to the press notes for season four, Otis is now 17.

Emma Mackey plays Maeve Wiley, a rebellious student who has had a difficult upbringing. In the fourth season, she has gone to a writing program at Wallace University in America.

According to the press notes for the show, Maeve is now 18.

Ncuti Gatwa plays the fan-favorite character Eric Effiong, a proud gay student who is figuring out his identity. He is also Otis' best friend and is likely to be between 17 and 18 since the pair have been in classes together in previous seasons.

In season four, Eric also attends Cavendish to complete his A-Levels.

Adam Groff, played by Connor Swindells, was a former bully of Moordale and an ex-boyfriend of Eric. In the fourth season, he decided not to return to school and instead find a job. Adam is also likely to be between the ages of 17 and 18 in season four.

Aimee Lou Wood coincidentally plays a character called Aimee Gibbs. Aimee is a close friend of Maeve and is another Moordale student who joins Cavendish College. She is likely to be between the ages of 17 and 18 too.

Jackson Marchetti (Kedar Williams-Stirling) is another Moordale student who has to transfer to Cavendish in season four. He is a former flame of Maeve and is still reeling from being rejected by Cal Bowman.

Jackson is also likely to be 17 or 18 since he has shared classes with the other Moordale students.

Ruby Matthews (Mimi Keene) was part of the mean popular group at Moordale. However, she is the only member to attend Cavendish in season four, hence she is forced to make new friends.

Since Ruby shared classes with the other Moordale lead characters, she is likely between the ages of 17 and 18.

Viv Odusanya (Chinenye Ezeudu) was introduced in season two as a study-focused student who befriends Jackson when they are forced to study together. Viv also transfers to Cavendish in season four, and is likely 17 or 18 in this final season like the other students. 

Cal Bowman (Dua Saleh) was introduced in season three as a non-binary student who joins Moordale and befriends Jackson. In season four, Cal joins Cavendish and struggles with their transition.

According to press notes for the season, Cal is 18. Saleh, who is also non-binary, is ten years older than the character they play.

Jean Milburn (Gillian Anderson) has been one of the main central adult characters since season one. In this season, she is trying to balance a new career opportunity with raising Otis and her newborn baby Joy.

According to the HuffPost, Jean was 48 in season three. Since season four appears to take place a few months or weeks after season three, she is likely between the age of 48 and 49.

At Cavendish College, Otis' main rival is O (Thaddea Graham), who had already established a sex clinic on campus. According to the press notes for season four, O is 17.

Jean's sister Joanna (Lisa McGrillis) is introduced in the final season as she comes to try and help the struggling mother with taking care of Joy. According to the press notes for the show, Joanna is 42.

At Wallace University, Maeve is taught by a successful author Thomas Molloy, who is incredibly hard on the students. According to the press notes, Thomas is in his late 30s.

"Sex Education" creator Laurie Nunn said they wrote Levy's character for him after said in an interview that he liked the show.