The average UK worker is putting in over 13 extra working days a year, with one in four working for 34 days more than they're paid.
Data from the CV-Library job board makes it clear that the days of the traditional nine-to-five are long gone, with two thirds saying they work longer than they're supposed to and one in 10 working every day of the week.
And despite 87% believing that every business should offer flexible working, nearly three quarters say they still don't have the option to work from home.
"It's become clear from the data that UK workers are putting in too much overtime. It's concerning to learn that up to one in 10 are even working seven days a week," says Lee Biggins, founder and managing director of CV-Library.
"Though technology may be great for enabling flexible working, it could also be disturbing the work-life balance of the nation's professionals as they continue to do work-related tasks outside of office hours."
Other countries have made moves to try and minimise the way work bleeds into family time. At the beginning of this year, for example, French workers won the right to ignore work emails out of hours.
Sweden, meanwhile, has been trialling six-hour days to see if this would increase staff productivity.
This is also something that the Green Party's keen on: in its May manifesto, it promised a four-day working week, with nobody having to work more than 35 hours overall.
The CV-Library survey found that three quarters of UK professionals would prefer a four-day working week, with over a third believing it would make staff more productive. Four in ten, though reckoned it might be stressful.
"It's clear that many believe that UK professionals would benefit from a four day week, despite there being mixed feelings around the subject," says Biggins.
"One thing is for sure, UK workers are at risk of becoming overworked if they continue to put in so much overtime and it's time they found themselves a healthier work-life balance."
The best jobs in the world
The best jobs in the world
What qualifications do you need? If you're a fan of Disney, between 5'4" and 5'"7, a size 10 and between 18 and 27 you might be in with a chance of becoming a Disney Princess! The role pays £11 an hour and you need to be an excellent public speaker and good with children.
Did you know? Tinkerbell and other fairies have a specific height requirement of between 4'11" and 5'2"
What qualifications do you need? Are you dexterous with great attention to detail and the ability to follow instructions? Then you could become a senior Lego sculptor in Denmark while being paid £8.20 an hour!
Did you know? Legoland Windsor is made up of 55 million bricks.
This has to be the perfect role for adrenaline junkies and rollercoaster lovers around the world. What qualifications do you need? All you need is a strong stomach, a passion for travel and be happy with doing your dream job for free.
Did you know? Kingda Ka in Six Flags Great Adventure, USA, has the record for world's longest rollercoaster drop.
What qualifications do you need? Well, you'll need to be able to swim, obviously. If you're lucky, you could be paid £20,000 a year to splash around on the slides.
Did you know? Action Park in New Jersey holds the world record for having the longest water slide at 2000ft long.
What qualifications do you need? If you're resourceful, can swim and snorkel and love making new friends, then island keeper may be the career for you and you could make as much as £78,000 doing it!
Did you know? The original Island Keeper was Brendon Grimshaw who purchased Moyenne Island in 1964 for $20,000, it's now worth millions.
What qualifications do you need? You'll need to be physically fit, have a SCUBA certification and a bachelor's degree in an animal-related field to become an animal trainer but you could earn £20,850 doing it.
Did you know? Dolphins can stay alert for more than 15 days by sleeping with one half of their brain at a time.
What qualifications are needed? A sweet tooth is a distinct advantage for this this £41,000 per annum ice cream tasting job - but isn't as easy as it may sounds. As well as healthy taste buds you'll need a Bachelor of Science degree in dairy science or food science too.
Did you know? John Harrison has been a professional ice cream taster for 30 years and has tried nearly 200 million gallons of ice cream.
What qualifications are needed? You'll need dive theory knowledge, first aid skills and Padi certifications before you'll be allowed to take to the seas and earn £27,500 as a senior scuba instructor, but it's worth all that training for a life in the Caribbean.
Did you know? Once you get below 10 metres depth while scuba diving you can't see red or yellow. If you cut yourself your blood will look blue.
What qualifications do you need? To become a £36,500 per annum Great Barrier Reef caretaker you'll need a love for wildlife, adventure, a BSc in Marine Biology and resourcefulness.
Did you know? The venom of the Australian box jellyfish is considered to be among the most deadly in the world.
What qualifications do you need? Very good fitness levels.If you've always wanted to go 'Down Under' and have a passion for nature and the outdoors as well as a sense of adventure and resourcefulness then a £52,000 per annum career in the Outback may be just right for you.
Did you know? The Australian outback is more than 2.5 million square miles in area and is home to several different climate zones.
Calling all big kids out there! If being imaginative, thinking like a child and dreaming outside the box sounds just like you then you should volunteer as a toy tester!
Did you know? Top 'mum bloggers' can earn up to as much as $250 for a review.
Being a chocolate taster may sound like a dream job but it could become reality if you have a serious sweet tooth, love of chocolate, cultured palate! No smokers allowed for this £35,000 job because it ruins your tastebuds.
Did you know? Humans have around 7,500 taste buds in their mouths.
Unbelievably dog surfing coach is actually a real job and you could earn as much as £51 an hour doing it if you're great with animals, SGB/ISA approved and love the outdoors.
Did you know? Hungtington Beach in California isn't just a hotspot for human surfers. For the last five years it's played host to the Annual Surf City Surf Dog contest!
What qualifications do you need? Being physically fit with a strong knowledge of coconut trees and risk management could land you a £17,061 per annum job these days!
Did you know? 150 people die every year from falling coconuts.
If you're wondering what job you can use your BA in structural, electrical and mechanical engineering for and earn £60,000 we might have the answer - become a rollercoaster engineer!
Did you know? One of the most famous rollercoaster engineers had intense motion sickness and couldn't go on more than 80 of the rides he had designed.