Pre-qualification for a loan or mortgage is an important step in the home buying process. It can give potential buyers insight into their finances and how much they can afford to spend on a house. The length of time that a prequalification remains valid, however, varies by bank. Generally, banks will provide a prequalification that is good for 90 days which gives ample time to search for the right property and begin the loan application process. It's important to remember that, even if you have been prequalified, your financial picture may change over this period and lenders should be contacted again at least every 30 days for updates. Keeping lenders informed of any changes can help ensure you maintain access to the best loan terms available.