Definition
Cost of capital buffer is the extra return you require above the base cost of capital to cover model risk and uncertainty.
Formula
Target return = cost of capital + buffer
Example
If WACC is 10% and buffer is 3%, target return is 13%.
How to use it
- Use larger buffers for volatile cash flows or new markets.
- Document buffer logic to keep decisions consistent.
Common mistakes
- Applying the same buffer to low-risk and high-risk projects.
- Double-counting risk if the discount rate already includes it.
Measured as
Target return = cost of capital + buffer
Misused when
- Applying the same buffer to low-risk and high-risk projects.
- Double-counting risk if the discount rate already includes it.
Operator takeaway
- Use larger buffers for volatile cash flows or new markets.
- Document buffer logic to keep decisions consistent.
- Tie Cost of Capital Buffer to the same balance-sheet date, scenario, and decision memo you are using elsewhere in the model.
- Document which claims, costs, or adjustments your team includes before comparing numbers across forecasts, covenants, or valuation work.
Next decision
- Read WACC explained: how to estimate a discount rate for DCF if the decision depends on interpretation, policy, or trade-offs beyond the raw formula.
- Decide whether Cost of Capital Buffer belongs in cash planning, valuation, or debt monitoring so the number is used in the right model.
Where to use this on MetricKit
Guides
- WACC explained: how to estimate a discount rate for DCF: A practical guide to WACC: what it is, how to compute it, and how to use it (carefully) as a DCF discount rate.
- Investment decision metrics: NPV vs IRR vs payback vs PI: A practical guide to investment decision metrics: when to use NPV, when IRR misleads, and how payback and profitability index fit in.