The consistency principle requires accountants to be consistent from one accounting period to another in applying accounting principles, methods, practices, and procedures. In other words, the readers of a company's financial statements can presume that the same rules and measurements were followed in all of the years being reported. If a change is made to a more preferred accounting method, the effects of the change must be clearly disclosed.

The Financial Accounting Standards Board refers to consistency as one of the characteristics or qualities that makes accounting information useful.