Cool Loser: Zigzagged. When he actually picks up (or at least is close at picking up) girls, it's usually because they fall for his peculiar humor or pertinent sarcasm. But most of the time, these traits just make people consider him to be a pompous/awkward freak.
Cunning Linguist: Is the only member of the group that has any knowledge of any language other than English (as shown by his conversation in French with Patrice). Downplayed, though, as he doesn't find himself in any other situations where other languages are needed (if he knows any) and justified in that he's probably studying French for his A levels.
Deadpan Snarker: Particularly in the narrations. In fact, it's what women find most attractive in him.
Digging Yourself Deeper: Has a tendency to keep going off on tirades long after he should have stopped, most notably in his rebuffing of Kerri.
The mechanics at the garage are reasonably friendly towards him...until Will starts telling them he's "too clever" for their job.
Disappeared Dad: His father leaves his mother prior to the start of the series, meaning that she can no longer afford to send him to the private school he was attending previously, forcing him to go to Rudge Park. He doesn't make an appearance until the first movie.
Hair-Trigger Temper: Tends to go off into a massive rant at relatively minor things such as people taking the front seats on a roller coaster, being denied alcohol or being assumed to be in a relationship with a girl he has no interest in.
Has a Type: Most of the women he has been attracted to over the series and movies - Charlotte, Lauren, Alison and Katie - have been blonde. Katie and Alison look similar enough that some fans mistook their actresses for the same person.
The Hero: By default, being the main character and all. He himself doesn't have any heroic qualities.
Kavorka Man: While he's not unattractive, he's not handsome by any means, dresses like a ninny and acts like an awkward stick in the mud at all times. Despite this, several attractive girls have shown interest in him. Subverted to a degree in that he tends to lose their interest because of these very flaws, making it a mystery of how he attracts them in the first place.
Not So Above It All: While he generally attempts to behave more grounded and rationally minded than most of his friends and is clearly more responsible in the majority of situations, there are several incidents that prove he is effectively capable of the same level of thoughtlessness and ineptitude. Most evident when he's left home alone, he eventually joins in with the lads in destroying daffodils after a few cans.
Of Course I'm Not A Virgin: Blunders it with Charlotte, telling her that he slept with an 11-year old when he was 13. She figures out that he's a virgin during his attempts to have sex with her and, thus, ruins his chances with her. Subverted in the first movie when he's honest with Alison about being a virgin. She doesn't think any less of him for it.
Only Sane Man: Not as much as Simon is, but he's comparatively normal when alongside the other two.
The Smart Guy: Somewhat subverted in that he's while he's academically bright and smarter than the other three, he often reveals his limited amount of social skills and general impulsiveness in particular situations.
Socially-Awkward Hero: He could be interpreted as this as he has undertaken some misguided deeds that express his ultimate lack of understanding certain societal norms. Such as:
Vocally complaining when a group of people were seated at the front of a ride he and his friends had specifically queued for, only to find out said people were obliged to take this space in the ride as they were disabled.
Somewhat justified, in that he had no knowledge of their disability, having never previously seen these people, and he also showed extreme remorse for these actions.
Impulsively placing a wig within his underwear during a date with an older woman, after a prank lead to his own pubic hair being removed, causing further embarrassment for him.
Attempting to amiably break off an effectively one-sided relationship with a girl he was never attracted to, only to create a scene during his friend's birthday party.
This was partly the girl's fault; she had manipulatively claimed that Will attempted to have sex with her, prior to breaking off the "relationship".
Becoming the subject of abuse after making several pretentious, patronising but ultimately not malicious claims towards a group of garage workers he would be employed by during his work experience.
Claiming to have engaged in several sexual encounters in order to secure his relationship with a slightly older, promiscuous girl, only to face more severe humiliation when his lack of sexual experience is evidenced.
Making wild claims of said girl's opinion of him and an extreme exaggeration of their "relationship" to avoid being further abused by the afore mentioned group of mechanics.
Surrounded by Idiots: He is academically more knowledgeable than his three friends and usually more grounded uptight and sensible than them (other than possibly Simon, as the voice of relative sanity alternates between the two characters depending on the situation)while he has his own moments of tactlessness, he is generally among the most rationally minded and logical of characters in the series.
Chick Magnet: Women do tend to be into him, but he'd have much more success if he wasn't so hung up on Carli the whole time. Tellingly, of all the lads, he's the one who's been in the most actual relationships.
Cool Loser: While the other three have traits that make their lack of popularity understandable, Simon is a nice, handsome and funny guy who tends to have the most chances of climbing the social ladder presented to him, only to fail due to publicly humiliating himself.
Deadpan Snarker: Not to the same degree as Will, but his Only Sane Man status makes him have his moments. Like Will, he especially loves saying "brilliant".
Extreme Doormat: He seems to be this to his Love Interests quite a lot- he only confronts Carli about her casually using him at the end of the first movie, is resigned to Lucy's crazy behaviour in the second and lets Tara dress him up "like an eccentric posh child", in Will's words.
Hopeless Suitor: To ridiculous levels with Carli. He's pined for her since he was eight years old and doesn't get anywhere with her until the end of series 2, and even then, she doesn't really care about him.
It's All About Me: When his father tells him that the family will need to move to Swansea so he can keep his job, Simon goes mad, claiming that his life is ruined as a result.
Not So Above It All: Along with his ridiculous behavior around Carli, Simon acts like a complete asshole to both of his parents at all times despite them easily being the most normal parents on the show.
Abusive Parents: His Dad belittles him in almost every conversation he has in the series and his mother just sits there and lets him.
Attention Whore: He admits to Big John that he makes up lies so people will notice him.
All Men Are Perverts: He will make lewd comments about every woman going and sometimes, depending on how much he's drank, make unwanted sexual advances. However, this trope is subverted whenever he meets a girl he actually cares about.
Disrespecting a girl he fancies seems to be one for him- he gets quite angry at the end of the first movie and during the second when people make fun of Jane's weight. He also gets mad with Neil when he makes lewd comments about Chloe.
Determinator: In the second movie, he goes to Australia, where he has to work in a toilet and sleep in a tent, to try and win Jane back.
Dirty Coward: Often; he immediately tells Donovan that Will is upstairs with Charlotte, mocks Simon after some guys threaten to beat him up over something Jay did, ditches his friends when some chav pre-teen girls get their brother to chase them with a cricket bat...
Miles Gloriosus: One of his many Blatant Lies is that he once spent the summer at a Thai boxing training camp and knocked out so many Thai fighters that they had to bring in fighters from Cambodia. Of course, it's obvious that he has no experience.
The Nicknamer: Almost never calls Will by name in the first two series, but instead some variation of "briefcase". In the third series, when Will becomes more known for shitting himself at an exam than carrying around a briefcase, Jay starts calling him by name, though still lets slip a briefcase insult/joke once in a while.
Of Course I'm Not A Virgin: Constantly brags that he's shagged every woman he's ever come across, sometimes several at a time. Taken Up to Eleven in the second movie when he claims to have had a three way with the Minogue sisters ten minutes after arriving in Australia. His Establishing Character Moment even has him bragging that he's really good at shagging only to trip up on a question Neil asks.
Sir Swears-a-Lot: Probably has the filthiest mouth out of the lads, although they have their moments too.
Sticky Fingers: "I nicked it out of Sadie Cunningham's bag during registration" appears quite a few times in the show.
Super Gullible: In addition to spouting Blatant Lies, Jay is more than willing to believe them as well. This includes the rumour that a sexy housewife in Swannage is willing to have sex with schoolboys and when the trio of drunk students tell him about Dutch student Heike wanting to have sex with younger guys.
Token Evil Teammate: Evil is a strong word, but most of the time, Jay isn't actually nicer than school bully Donovan - the main difference simply is that Jay is too big of a coward to use violence. His jerkassery is played more for laughs than Donovan's, though, but except for his very few Pet the Dog moments, he only seems to be part of the group by virtue of having known Simon since early childhood and being admired by Neil who is stupid enough to believe in his lies.
There's also the fact the lads are clearly aware of Jay's Freudian Excuse - Simon even accuses Jay of being scared of his Dad in the movie. Donovan on the other hand mostly seems to act like a dick For the Lulz.
What You Are in the Dark: When he talks alone with Big John in the sixth episode, he shows a surprisingly nice side of himself and even seems to find John sympathetic. However, when others are around, he doesn't miss one chance to gravely insult John, especially about his weight - because the general consensus is that John is a loser.
"Well Done, Son!" Guy: A lot of his lies are to impress his Dad, but his Dad is Genre Savvy enough that he doesn't fall for it. Unfortunately, he then tends to respond to Jay's attention seeking by belittling him. This seems to create a Vicious Cycle - Jay tells more lies to impress his hard-to-please Dad, who as a result tries harder to puncture his son's inflated ego. It's not known whether the chicken or the egg came first.
Played by Blake Harrison
Anything That Moves: He's not fussy about who he winds up with, which is probably why he's the first of the lads to lose his virginity.
Bitch in Sheep's Clothing: It's hard to tell if he's this or simply so dumb he does mean things by mistake, but he's pulled some very dick moves over the course of the series.
Catch Phrase: He adopted saying "No problemo" in a shit Spanish accent for one episode, but dropped it afterwards.
He tends to say "behave" when the others say something that annoys him.
Cloud Cuckoo Lander: Particularly when he goes on about how many things are drugs, starting with relatively sane things such as cigarettes and alcohol and moving on to stuff like trainers and clingfilm.
Hot for Teacher: Has a crush on Miss Timms and makes a move on her at the end of the first series.
Kavorka Man: Not that he's "ugly" per se, just very stupid with lacking hygiene.
Likes Older Women: Not only Miss Timms but also the older women around Malia in The Movie. He hooks up with an older housewife in the second movie too.
Nice Guy: Neil can be annoying due to his stupidity, but he has almost no actual Jerkass moments compared to the other lads. He is also generally polite and is quick to comfort his friends in the "arm around the shoulder and kind words" way that the others would probably deem as too "bent" or girly. Although hooking up with a new girl in the movie and cheating on his current girlfriend with a transparent excuse, ignoring her when she was waiting for him at the airport when returning from Greece in the first movie is a definite contradiction.
Not So Different: Despite hating Will with passion most of the time, he genuinely agrees with him when Will argues that a fashion show is a stupid, unethical way to collect money for charity since only good-looking people are able to take part. However, he is still enough of an asshole to force Will to take care of the charity money anyways.
Pet the Dog: Neil mentions Gilbert takes him making a move on Ms. Timms after one too many beers quite well.
He also stops Paedo Kennedy from molesting Neil on a couple of occasions, even telling Kennedy that he's been putting his neck on the line for him.
Sadist Teacher / Apathetic Teacher: The former against students who have managed to personally annoy or insult him, especially Will. The latter against students in general.
Sitcom Arch-Nemesis: Will gets on the wrong side of him on his first day and he never lets up at him, even after he leaves the school.
Sequel Non-Entity: She has vanished from the face of the earth in the second movie. While she was Put on a Bus at the end of the first movie for perfectly justifiable reasons, it's still a bit jarring as she was one of the most important characters of the show before with so many of the plots and sideplots being about Simon trying to win her heart.
The Tease: When Simon stops paying attention to her and starts getting interested in Lauren, all Carli has to do is compliment him and he instantly forgets all about Lauren.
Took a Level in Jerkass: She's a reasonably nice Girl Next Door in the first series, but later on appears to be just stringing Simon along and even using him to make other guys jealous when it suits her.
Hidden Depths: When he sees Will being grappled by Donovan at the Christmas party, he doesn't even hesitate before yelling at Donovan to put him down, which gets the whole school year to stick up for Will and Donovan to back off.
Kavorka Man: Is seen at a house party with his hand on a girl's breast.
Straw Loser: He often appears when the four main characters seem to be complete losers to point out that they are actually not at the bottom of the hierarchy (there is a reason they're called "inbetweeners" - they're not really losers, at least not if they pull themselves together, but they are surely not popular either), because guys like John are much worse off.
However, it's inverted in the episode "Will's Birthday" where the fact that even John is invited to a party shows how uncool the four main characters are.
Although, when confronted, the girl in question says the only reason she didn't invite the lads simply because she didn't know them that well.
Brainless Beauty: As of the second movie. While she's always had a certain cluelessness she has clearly taken a Level In Dumbass, accidently flashing everyone her cleavage while trying to adjust her webcam amongst other things.
The Comically Serious: Or The Cringe Comically Serious if you want. Whenever he goes into unnecessary details about his sex life, he often has a completely deadpan face as if he thinks mentioning his sex life is just like discussing politics. This tends to embarrass Simon even more.
Reasonable Authority Figure: He waits to hear Simon's side of the story when Simon accidentally climbs into Carli's little brother's room and professes love to him.
Hypocritical Heartwarming: Surprisingly, he gets one in the second movie when he starts a fight with his cousin, when he repeatedly insults Jay in front of him. Bearing in mind, Jay's dad usually says similar things to Jay, apparently only he is allowed to do so.
Jerkass: The main things he does in the movie is running over Simon's leg with a scooter (pretending it was an accident), conning Simon out of his clothes to humiliate him, threatening Jay (who was just trying to make friends with him) to beat him up, insulting Jane for being fat, and forcing Jay to give him a note so that he can sniff cocaine.