An affidavit is a written statement. A person, known as the affiant, swears under oath to the statement's truthfulness.The purpose of a sworn statement, for any purpose, is to try to get the person making the statement to be honest, through the idea they could be prosecuted. When you sign a sworn statement, you swear that no one other than those listed in the statement needs to be paid for the project. Look at what a contractor's affidavit is, when it's required, and the difference between an affidavit and a sworn statement. Affidavits, or notarized sworn statements, are used to swear that any written statement or fact is legally valid. However, there is one main difference between the two documents. A sworn statement is a construction document that lists the contractors and suppliers that provide material or labor to a construction project.