Pre-Approval explained
Pre-approval is the lender's early assessment of how much you can borrow. The lender reviews your income, employment, existing debts, credit score, and down payment, then states a maximum mortgage amount and a rate it will hold for a fixed period, commonly 90 to 120 days. This rate hold protects you if rates rise while you search, and the dollar figure sets a realistic budget before you start viewing homes.
A pre-approval is conditional. Final approval still requires an accepted offer on a specific property, an appraisal, confirmation that the home meets the lender's criteria, and verification that your finances have not changed. It is stronger than a quick pre-qualification, which is only a rough estimate, but it is not a guarantee that the mortgage will fund.