Finance

Capital Structure

Capital structure is the mix of debt and equity used to finance a business. It drives risk, flexibility, and the weighted cost of capital.

Updated 2026-01-28

Definition

Capital structure is the mix of debt and equity used to finance a business. It drives risk, flexibility, and the weighted cost of capital.

Formula

Debt ratio = debt / (debt + equity)

Example

If debt is $2M and equity is $3M, the debt ratio is 2 / 5 = 40%.

How to use it

  • Match debt levels to cash flow stability and downside risk tolerance.
  • Revisit structure after large funding rounds or major capex plans.

Common mistakes

  • Assuming a single target ratio fits every business stage.
  • Ignoring covenants and refinancing risk when adding leverage.

Measured as

Debt ratio = debt / (debt + equity)

Misused when

  • Assuming a single target ratio fits every business stage.
  • Ignoring covenants and refinancing risk when adding leverage.

Operator takeaway

  • Match debt levels to cash flow stability and downside risk tolerance.
  • Revisit structure after large funding rounds or major capex plans.
  • Tie Capital Structure 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 Capital Structure belongs in cash planning, valuation, or debt monitoring so the number is used in the right model.

Where to use this on MetricKit

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