Broadband speeds in the UK are around 35 per cent slower at peak times, research from uSwitch shows.
The study, based on two million speed tests across the UK, found the fastest average download speed of 9.6Mbps is only available between 2am and 3am.
During the peak surfing hours of 7pm to 9pm, average download speeds fall to 6.2Mbps, the slowest of the day.
In Evesham, Worcestershire, a massive fall of 69 per cent takes place during peak hours, with average morning speeds of 15.5Mbps declining to 4.9Mb/s in the evening.
Not many internet users enjoy the maximum headline broadband speeds offered by providers, and certainly not during the working week.
Weston-Super-Mare, Somerset, showed speeds falling by almost two-thirds between off-peak mornings and peak evening times, from 9.5Mbps to 3.4Mbps.
In Wadebridge, Cornwall, the speeds drop from 4.1Mbps during off-peak hours to a low of 2.1Mbps in the evening.
"It really is surprising just how much broadband speeds fluctuate at different times of the day, with drop-offs of almost 70 per cent in some areas of the UK," said Ernest Doku, technology expert at uSwitch.com.
"Not many internet users enjoy the maximum headline broadband speeds offered by providers, and certainly not during the working week."
Reasons for surfing the web have changed over the years, with more people downloading music and watching TV shows online. Research shows that this also adds more strain to the network.
"It is important to remember that the fastest headline speeds are not guaranteed and home broadband users should perform an online broadband speed test to check that they are getting the best possible package for their area," said Doku.
There is a long road ahead to ensure that everyone can enjoy a much more consistent broadband service, uSwitch added.
