Unearned revenue, also known as deferred revenue, refers to the cash advance paid by a customer before receiving goods or services. The concept of unearned revenue is commonly used in accounting to classify funds that are yet to be earned. Synonyms to this term include deferred income, prepaid revenue, or advance payment, and they all refer to a similar concept of revenue recognition. Deferred income is a liability since the cash has already been received from the customer, but the service or good is yet to be delivered, resulting in a deferred revenue account. The use of these synonyms depends on the type of business and the accounting practices used.