Understanding Cost Overrun Percentage
How we calculate. Overrun % = (actual − budget) ÷ budget × 100 (negative = under budget). The form uses the same arithmetic as the worked examples on this page. See our methodology and accuracy policy.
Real-world scenario: A typical Cost Overrun Percentage case uses actual cost 11200000 and budget 10000000. Enter the same figures below to reproduce the worked path.
What is Cost Overrun Percentage?
A simple budget variance KPI. Distinct from CPI/CV on the Professional hub, which use earned-value formulas.
- Same cost basis (committed vs incurred)
- Positive = over budget
- Cross-link CPI for EV cost performance
The Formula
Worked Example
Common Use Cases
- Cost reports: budget burn
- Forecast reviews: overrun risk
- Package compare: trade overruns
Pro Tips
- Freeze the budget baseline
- Separate approved COs from true overrun
- Use CPI for EV analytics
Limitations: Cost Overrun Percentage results are educational construction planning aids—not engineering, safety, legal, or cost-estimating advice. Confirm definitions with your project controls, safety, and contract documents. For earned-value SPI/CPI see the Professional hub.
FAQ
Same as cost variance %?
Related idea, different formula family. Professional CV/CPI use earned value; this page is actual vs budget only.
What if budget is 0?
Overrun % is undefined—enter a positive budget.
Authoritative References
For construction project controls and safety rate concepts, consult: