Men finally grow up at the age of 43 – a full 11 years after women 'mature', according to a new survey.
A study into the differences in maturity between genders revealed both men and women agree men remain 'immature' well into their late 30s and early 40s.
But the average age at which women mature emerged as 32.
Alarmingly, eight out of ten women believe that men 'never stop being childish' – with breaking wind, burping, eating fast food in the early hours and playing videogames their biggest bug-bears.
Staying silent during arguments, not being able to cook simple meals and re-telling the same old jokes and stories when with the lads were also hailed as signs of immaturity.
The research was commissioned by Nickelodeon UK to mark the launch of the new show Wendell & Vinnie showing weeknights at 7:00pm.
Tim Patterson VP, Director of Programming, Nickelodeon UK, said: "As a man, especially one who works for a children's channel, the question if men ever reach maturity is one I am well accustomed to.
"However as the characters Wendell and Vinnie show in our new programme, a difference in maturity between two people definitely makes for an amusing partnership."
Both men and women agreed women reach proper maturity much earlier than guys, at the typical age of 32.
Men were nearly twice as likely to describe themselves as immature than were women with one in four men believing they are actively immature.
Women were also twice as likely as men to feel that they were the 'grown up' one in their current relationship.
One quarter of women felt they were the ones made all the important decisions in the relationship with the same percentage wishing their partner would talk about themselves and what they're feeling more often.
Women also found British men's biggest maturity failings were still finding breaking wind funny, driving too fast and playing videogames.
Three in ten women have ended a relationship because they lost patience with the guy being too immature.
A whopping 46 per cent of women have had a relationship in which they felt they had to mother their partner a bit too much.
In fact the average British woman has to tell her cheeky partner to 'act his age' more than once a month – an average of 14 times a year.
Immaturity does have it upside though with four in ten people think immaturity is important in a relationship because it ensures the partnership stays fun and keeps things fresh.
One in three people think a bit of immaturity helps in bonding well with children.
The brand-new, comedy series, Wendell & Vinnie, follows 30-year-old Vinnie Bassett, a carefree bachelor, who suddenly becomes the legal guardian of his wise-beyond-his-years nephew Wendell.
Vinnie's bachelor life comes to a halt when he assumes guardianship of his incredibly intelligent and mature nephew, Wendell. They soon find that 12-year-old Wendell may be just the parent Vinnie needs. The series will air regularly every weeknight at 7:00pm on Nickelodeon.
MEN'S TOP 30 MATURITY FAILINGS
1.Finding their own farts and burps hilarious
2.Eating fast food at 2:00am
4.Driving too fast or 'racing' another car at the lights or on the motorway
5.Sniggering a bit at rude words
6.Driving with loud music
7.Playing practical jokes
8.Trying to beat children at games and sport
9.Staying silent during an argument
10.Not being able to cook simple meals
11.Re-telling the same silly jokes and stories when with the lads
12.Don't like talking about themselves/ having proper conversations
13.Hating books/reading because of short attention span/they're boring
14.Doing crazy dance moves
15.Mum still doing their washing
16.Having their Mum still make them breakfast/any meal
17.Wearing trainers to night clubs
18.Owning a skateboard or BMX
19.Not eating vegetables
20.Changing jobs regularly
21.Getting too excited over stag do's
22.Sometimes trying to do wheelies/stunts on their bike
23.Driving a modified car or one with a loud exhaust/boy racer
24.Showing off about how girls are attracted to them
25.Wearing pyjamas, specifically cartoon pyjamas
26.Using dodgy chat-up lines
27.Showing off about protein shakes/weight-lifting/how much they 'lift'
29.Wearing saggy-crotched jeans
30.Having a cartoon bedspread