A survey of 2,000 men and women aged 24 to 39 revealed more than a third (36 per cent) are spending more time visiting homeware stores than socialising with others.
Two thirds (66 per cent) get a sense of excitement when they buy new items for their property.
But while it’s nice to have good decor, a third of respondents (34 per cent) said they get a bigger buzz from buying clever cleaning products than buying furniture.
Almost half (49 per cent) of millennials – who are less Kate Moss and more Mrs Hinch – admitted they would rather spend their money on homewares and accessories for their home than go for a night out with friends.
As a result, 50 per cent of respondents regard themselves as 'geri-lennials' - a young person who behaves much older than their age.
A spokesman for online marketplace OnBuy.com, which commissioned the study, said: “While millennials have a reputation for living a party lifestyle and having a great time into the early hours of the morning, the reality appears to be somewhat different.
“Given the opportunity, they’re likely to prefer a relaxing evening with a good book and a slice of home baked cake than a night on the tiles.
“A lot of this is down to their desire to enjoy the home they live in and have spent time decorating and ensuring it’s spotlessly clean.
“Our love of stylish homeware and a fondness for scrolling through other homes online is helping to ensure millennials enjoy the quieter life in the best possible setting.”
The research revealed the average millennial typically spends £111 per month enjoying leisure activities outside of the house.
But when it comes to what they'd rather do for an evening, nightclubbing sits beneath cleaning the home, gardening, playing board games, reading, and going to bed early.
And millennials are more likely to enjoy spending their cash on clothes, baking goods, home decor, home accessories and skincare than clubbing.
While clubs have been shown the door, socialising is important – they’re just eight times more likely to want to do it in a restaurant than a raucous venue.
To ensure their home is looking as sharp and fashionable as possible, they are spending £70 per month improving the interior.
When it comes to inspiration for home renovations and improvements, forget celebs and property TV shows, it's all about Pinterest and Instagram, followed by friends, going into physical stores and speaking to family.
They’re also typically spending one-and-a-half hours per week browsing homeware websites, according to the OnePoll research.
And millennials are a nosy generation as well - with 42 per cent admitting they spend more time than they should browsing homes on property portals despite not looking to move.
OnBuy.com, UK based online marketplace, has now launched a quiz to see if you’re a geri-lennial.
A spokesperson for OnBuy.com added: “It certainly seems that millennials’ best moves are more likely to be found on the shopfloor than the dancefloor as they do their best to enjoy the finer things in the comfort of their own home.”