A loan officer provides mortgage options only from the company that they work for, while a mortgage broker works with multiple mortgage lenders to secure the best options for you. In the simplest terms, a loan officer is akin to a salesperson for their company, while a broker works on your behalf to secure the best mortgage loan for your needs. There are many pros and cons to both, but if you are researching online mortgage lender options, you will primarily be working with loan officers.