Transmittal letters often accompany reports and inform readers of a report's context. Typically, the letter includes information not found in the report. For example, the letter contains information about the particular project and/or due dates. A Transmittal Letter is a business letter and should be formatted accordingly; that is, you should include the recipient's address, your address, a salutation and closing. Depending on the project, you may also need to include contact information. Always check with your instructor to determine whether or not you should attach a transmittal letter to your report.

In Finance, a Letter of Transmittal is a document used by a security holder to accompany certificates surrendered in an exchange or other corporate action.

A Letter of Transmittal may also be a distribution list with the recipients of a memo, report or contract.

A transmittal letter accompanies a document and explains what the document is, why it should receive the reader's consideration, and what the reader should do with it.

A transmittal or cover letter accompanies a larger item, usually a document. The transmittal letter provides the recipient with a specific context in which to place the larger document and simultaneously gives the sender a permanent record of having sent the material.

Transmittal letters are usually brief. The first paragraph describes what is being sent and the purpose for sending it. A longer transmittal letter may summarize key elements of the proposal in one or two sentences and provide the recipient with other useful information.

End transmittal letters with a one-sentence paragraph that establishes goodwill by thanking or complimenting the recipient.