Netflix confirmed the news back in July alongside the season 4 trailer.
But naturally, fans are still holding out hope for a surprise season, a Sex Education spin-off or a movie wrap-up.
So, why is season 4 the show's final instalment and will we ever revisit the Sex Education universe? Read on to find out.
Why won’t there be a Sex Education season 5?
Although it wasn't originally intended to be the show's last, season 4 is now going to be the final outing for Sex Education.
Announcing the decision to end Sex Education in a note shared via Netflix, Nunn wrote: "A lot has happened since our first writers room in 2017, when we spent a month in a cramped office above a sex shop, talking about what it felt like to go through puberty.
"We wanted to make a show that would answer some of the questions we all used to have about love, sex, friendship and our bodies. Something that would have helped our inner teenagers feel a little less alone.
"It's been overwhelming seeing how the show has connected with people around the world, and we hope it's made some of you feel a little less alone, too."
She continued: "Writing this feels bittersweet, as we've decided the fourth season will also be the final instalment of our show. This was not an easy decision to make, but as the themes and stories of the new season crystallised, it became clear that this was the right time to graduate."
Speaking to Netflix Tudum, Nunn also said that the decision to end the series with season 4 presented itself when herself and the writers started developing the scripts.
She explained: "During that process, it just started to feel very clear that the stories were coming to an end, the characters were being left in a place that I felt really good about it. I felt happy for them, and I felt like I’ve said everything that I want to say with these characters at this time."
It makes a lot of sense to end the series now as its stars have gone on to star in some major productions, with plenty more on the horizon.
The next year or so looks especially exciting for Gatwa, who will be the next lead role in Doctor Who at the end of the 60th anniversary specials. Gatwa previously told Rolling Stone UK that the cast had "outgrown" Sex Education, saying: "It was very hard; it was such a big show.
"When you’re telling stories that haven’t been seen before, there’s always a battle as to how to tell them. It wasn’t always joyous. I feel like we’ve outgrown it and we’ve given everything we can to it."
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Following his RadioTimes.com TV 100 win, Gatwa reflected on his time in the Netflix series, saying: "Being a part of that ensemble for four years was so special. I made some of my best friends and worked on a project that meant something special to people."
Other cast members who are also set for some exciting future projects include Aimee Lou Wood, who has been confirmed as one of the leads of new dark comedy film The Gambler Wife.
Similarly, Connor Swindells will be joining Gillian Anderson and Keeley Hawes in Netflix's Newsnight drama Scoop, as well as reprising his role as David Stirling in season 2 of BBC's SAS Rogue Heroes.
So, it's safe to say that, while we may not be seeing the cast in their Sex Education roles again, this certainly won't be the last we hear of them.
Will there be a Sex Education spin-off?
While there's long been mention of the cast's increasing ages and the fact they're depicted as teenagers on the show, series creator Nunn has said that there's definitely potential to explore more in this Sex Education world.
Speaking in an interview with Tudum, she said: "I’m definitely taking a break and thinking about other things, but Moordale is a really rich world, and writing about teenagers is always a lot of fun. So, I think that there’s always potential for more to be explored in that world."
As for now, there has been no further word on whether our beloved group of students could be getting a spin-off series - so we'll just have to wait and see.
Like this? You might want to try Outlander. Available now on Lionsgate+.
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