The average premium of a new-build home over a secondhand property is almost a third.
However, mark-ups can be as high as 108%.
The current average price of a new-build in the UK is £290,176, compared with £224,729 – a mark-up of 29%.
The highest premium is in Scotland with new-builds costing 41% more than existing homes, dropping to 36% in Wales, 27% in England and 25% in Northern Ireland.
In particular areas, the premiums soar. In Harlow, Essex, the average new-build costs £551,089, more than double the average secondhand price of £265,249.
Blaenau Gwent is the next worst area, with a 96% mark-up between the new-build price of £182,313 and the price of existing property (£92,814).
Gravesham in Kent ranks third with a 95% new-build premium, while in Preston, Lancashire, there is a new-build premium of over 90%.
Rochford and Torfaen in Wales both have a premium of 88%, followed by Middlesbrough (85%) and West Dunbartonshire in Scotland (85%).
Caerphilly and Merthyr Tydfil complete the top ten worst areas for new-build property price premiums in the UK at 81% and 80% respectively.
In London, there is barely any new-home premium, averaging just 3%, although Newnham has a gap of 38%.
The figures are from new research by quick buy company Springbok.
It comes as recent research by the HomeOwners Alliance found that 40% of new-build purchasers were unhappy with the snagging process, with over a third believing that faults were not corrected within two years.
Founder and CEO of Springbok Properties, Shepherd Ncube, said: “While there are many new-builds that will be delivered to the standard expected, the thought of forking out way above the odds for a property that falls way below standard is a nightmare scenario.
“As the figures demonstrate, in some areas new-build properties are going for a hefty market premium and this isn’t confined to one or two locations.
“One has to question the consistent failures of many property developers when delivering these homes to the standard promised while still charging such a high price compared to the rest of the market.”