A letter of explanation can clarify your financial situation and get you one step closer to qualifying for a mortgage. It's difficult to sound sincere in a form letter.Master the art of writing a winning letter of explanation for your mortgage application with our comprehensive guide. A letter of explanation is your chance to answer any questions a lender might have about your loan application. Clearly explain where the money has come from, where it is going, the gaps you have in your employment, or any other issues that your lender might have raised. Typically, mortgage lenders will request a letter of explanation when they want to know more about your income, employment or credit. Mortgage lenders might request a letter of explanation for various red flags that come up in underwriting. Learn how to write one, and download a template. A borrower who has a history of unemployment may have to explain such gaps in employment in order to reassure their mortgage lender enough to receive approval. Keep your explanation brief, specific, and to the point. 3.