A mortgage is a loan used to buy a property. You borrow money from a lender (like a bank or building society) and pay it back monthly, with interest, over a set number of years (typically 5–40 years).

You'll typically need at least 5–10% of the property's value. A larger deposit (e.g. 15–20%) can unlock better interest rates. Usually for each 5% increase in deposit size the interest rate will drop slightly.