Which document typically serves as a formal notice to begin work on a project?

The letter of intent serves as a formal notice to begin work on a project because it outlines the intentions of the parties involved to proceed with the agreement while also confirming the essential terms of the contract. This document is often used in construction to signify that a contractor can start expending resources on a project, such as mobilizing labor and equipment, even before the final contract is signed. This enables the project to commence promptly, thereby ensuring progress and preventing delays.

Other options, while related to project documentation, do not serve the same primary function. A contract amendment modifies existing terms of an already signed contract rather than initiating work. A change order is used to document any alterations in the scope of work or adjust costs and timelines after the project has already commenced. Work authorization typically pertains to granting permission to proceed with specific tasks but may not have the same formal breadth or intent as a letter of intent to start the overall project. Thus, the letter of intent is crucial in signaling the beginning of work in construction projects.