A mortgage preapproval typically expires after 90 days. Some lenders have shorter windows of 30 days or 60 days, and others longer, up to 120 days. If you chose to lock in your mortgage interest rate, this usually aligns with your rate-lock period. If you haven’t found a home within that time frame, it’s possible to easily get a new preapproval, provided your credit and financial picture hasn’t changed since you first got preapproved.