It was also found that the number of men buying alone has fallen, while the proportion of women purchasing a property alone has hardly changed.
Commenting on the findings, Ms Tucker said: "Buying together is a very sensible choice in terms of affordability.
"Not only for splitting the mortgage and the bills, but more cuddling up should save you on the heating."
John Charcol's research has come after a study by Abbey found that around five million homeowners in the UK are not on the most suitable mortgage deal for them.
The findings suggested that affected Britons could be spending around £5 a day on home loan overpayments, meaning £25 million is being wasted by not shopping around.
Click here to run an energy price comparison, and see if you could be paying less for your gas and electricity.