How to Calculate Budget at Completion — Formula, Example & Calculator
Managing project finances can be challenging, especially when you’re trying to keep costs under control and meet deadlines. That’s where learning how to calculate Budget at Completion (BAC) becomes essential. The Budget at Completion tells you the total planned cost of a project — helping you track spending, forecast future expenses, and measure performance accurately. Whether you’re managing a small team project or a large-scale construction job, understanding how to calculate BAC ensures you stay on budget and make smarter financial decisions from start to finish.
Calculate Budget at Completion (BAC)
Use this free online calculator to calculate Budget at Completion (BAC) for your project. It helps estimate your project's total cost at completion based on its current performance and spending trends.
📘 Formula for Budget at Completion (BAC)
Formula: BAC = (EV ÷ AC) × PV
Where:
PV = Planned Value
EV = Earned Value
AC = Actual Cost
This formula helps determine the total project cost expected at completion, considering the current cost efficiency.
🧮 Example of Budget at Completion
Let’s say your project data is as follows:
- Planned Value (PV): $50,000
- Earned Value (EV): $30,000
- Actual Cost (AC): $32,000
Now apply the formula:
BAC = (EV ÷ AC) × PV
BAC = (30,000 ÷ 32,000) × 50,000 = $46,875
✅ So, the Budget at Completion (BAC) is $46,875. This means your project is expected to cost $46,875 when completed based on current performance.
💡 Note: A lower BAC than the original budget indicates efficiency, while a higher BAC means the project may go over budget.
What Is Budget at Completion (BAC)?
Budget at Completion (BAC) represents the total budgeted cost for the entire project.
It’s the expected total cost of completing the work according to the initial plan.
In simple terms, it answers the question:
“How much should this project cost when it’s done?”
BAC helps project managers compare what was planned versus what has actually been achieved and spent so far.
Why Is BAC Important?
- Tracks Financial Health – It gives you a clear forecast of whether the project is on, under, or over budget.
- Improves Decision Making – Helps you make informed choices about spending and resource allocation.
- Early Warning System – Identifies cost overruns before they get worse.
- Supports Reporting – A key metric for performance reports and stakeholder communication.
- Planning
- Design
- Execution
- Monitoring and control
- Closing
To learn more about Earned Value Management and how BAC fits into project cost tracking, check out this detailed guide from the Project Management Institute
FAQs
Budget at Completion (BAC) is the total budgeted cost of a project when it’s completed. It represents the amount of money the project is expected to cost based on the initial plan.
You can calculate BAC using the formula: BAC = (Earned Value ÷ Actual Cost) × Planned Value. This formula helps predict the total cost of the project based on its current performance.
BAC is the original total project budget, while EAC (Estimate at Completion) is the forecasted cost based on performance to date. BAC stays constant, while EAC can change as the project progresses.
BAC helps project managers understand whether a project is on budget or at risk of overspending. It’s essential for financial planning, forecasting, and tracking performance efficiency.
You’ll need three key values: Planned Value (PV), Earned Value (EV), and Actual Cost (AC). These metrics are part of Earned Value Management (EVM) and are used to calculate BAC accurately.
No, BAC is set at the beginning of a project and remains constant. However, you can compare it with the Estimate at Completion (EAC) to see how your actual costs are tracking against your original budget.
BAC provides a benchmark for your total expected cost. By comparing it with actual expenses and progress, you can identify inefficiencies early and make data-driven adjustments to stay on track.
No, BAC can be used in both small and large projects. Any project with measurable costs and timelines can benefit from using the Budget at Completion method.
If your BAC is lower than your EAC, it means your project is projected to go over budget. You may need to analyze spending, adjust resources, or reduce costs to realign your plan.
Yes, you can use our free Budget at Completion (BAC) Calculator above to quickly estimate your project’s total cost based on Planned Value, Earned Value, and Actual Cost.
Managing a project budget isn’t just about tracking expenses — it’s about understanding the numbers that drive success. One of the most important metrics in project cost management is the Budget at Completion (BAC), which helps determine the total planned cost of a project. If you’ve ever wondered how well you understand BAC and other budgeting concepts, this quiz is for you! Test your knowledge, challenge your financial accuracy, and find out if you’re a true pro at managing project budgets.
