Although fixed mortgage rates are falling, they are only doing so for those with decent deposits, shows the research.
By contrast, the rates available to those borrowers with small deposits are increasing.
The average two-year fixed rate for a borrower with a 10% deposit has increased steadily since April 2009, now standing at 6.48%, the highest level since December 2008.
However, the average rate for a borrower with a 25% deposit now stands is 4.27%, the lowest level since July 2009.
Over a term of two years, this means that a borrower with a 10% down payment will pay £4,728 more than one with 25%.
A spokeswoman for Moneyfacts, says: “While lenders are slowly increasing the number of deals available to those with a small deposit, which should be good news for first time buyers, they continue to make them pay a heavy price.
“Lenders continue to cherry pick the best customers and appear to be actively discouraging borrowers with a small deposit from remortgaging.
“First-time buyers are being offered little incentive to enter the market and there are no real signs of things getting better for them anytime soon.”