What is in an engagement letter?

An engagement letter contains six standard parts: the scope of services, the fees and billing arrangement, each party's responsibilities, the timeline, liability limitations, and termination terms. It opens by naming the client and the engagement, and closes with both signatures.

The format is deliberately plain: a letter on the provider's letterhead, written in second person, You have engaged us to..., ending with a signature block the client countersigns. Start it by stating the relationship and the period it covers, then work through the six parts in order.

The scope paragraph earns the most attention. It quietly defines what is excluded: preparation of your 2026 federal return also means not the state audit that follows. Precise scope in a friendly wrapper is the whole art of the document.

This client engagement letter sample gives you that structure ready to fill.