What is budget at completion (BAC)?

Budget at completion definition 

Budget at completion (BAC) is a term commonly used in project management, referring to the total anticipated cost of a project once it has been completed. It provides a benchmark for assessing the project's financial performance and serves as a baseline for cost management. In the context of agencies, BAC is a crucial factor in client project planning, as it helps in understanding the total expected expenses, thus facilitating pricing strategies and profitability analysis. Here’s an example:

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Task and estimated cost:

  • Designing: $3,000

  • Content creation: $4,000

  • Advertising: $3,000

Total (BAC for the project): $10,000

The above outlines the estimated cost breakdown for a digital marketing campaign undertaken by an agency. The various tasks involved, such as designing, content creation, and advertising, are listed alongside their corresponding costs, culminating in a total Budget at Completion (BAC) of $10,000 for the project.

3 methods for determining BAC

Determining the Budget at Completion (BAC) requires a careful evaluation of various factors that can influence the project's total cost. Different methods can be employed based on the nature of the project, available data, and the specific requirements of the client. Here are three common techniques that agencies can use to calculate BAC, each with its unique approach and applicable scenarios:

1. Parametric estimation

Parametric estimation is a technique that involves using statistical relationships between historical data and variables (such as scope, capacity, or complexity) to calculate the BAC. By applying known parameters and previously established models, agencies can forecast the total budget for a similar project. This method should be used when there's a clear relationship between variables and costs, and adequate historical data are available.

2. Expert judgment

Expert judgment relies on the insights and knowledge of experienced professionals within the field. This method of determining BAC often involves consulting with experts who have managed similar projects or who have specialized skills relevant to the project's domain. It can be particularly useful when there is limited data or when the project's nature requires specific, nuanced understanding.

3. Analogous estimation

Analogous estimation involves using the actual costs of previous, similar projects as a basis for estimating the BAC of a new project. This method assumes that if a similar past project cost a certain amount, the new project's budget should be in the same range. It is often used in the early stages of a project when detailed information may not be available or when the project's requirements are similar to those of previous efforts.

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