A new study from Nationwide has shed light on why so many people miscalculate repayments on mortgages in the UK.
According to the research, three quarters of all British consumers don't understand what a percentage change in their repayment agreement means in terms of the amount they owe.
The group forecast that Brits are throwing away millions of pounds each year by not understanding these calculations.
A spokesperson for Nationwide said customers should make sure they constantly have the best deal.
He added, "A £4,000 plus saving on a five-year deal for a couple of hours of work is a pretty good return!"