A project budget is the estimated financial plan for a project, for which funding is required. This document should include the expenses you anticipate to incur for a specified period of time, as well as earned income that will be generated during the course of the project. The budget is an important component of a proposal, as it represents a financial picture of the project. A well-crafted budget can add greatly to the grantmaker's understanding of your project.
Depending on the funder's guidelines, the budget may be a simple one-page statement of projected expenses, or an entire spreadsheet including projected support and revenue and a detailed narrative, which explains various items of expense or revenue.