Glossary term
Capital Adequacy Ratio (CAR)
The capital adequacy ratio, or CAR, compares a bank's regulatory capital with its risk-weighted assets.
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What Is the Capital Adequacy Ratio (CAR)?
The capital adequacy ratio, or CAR, compares a bank's regulatory capital with its risk-weighted assets. It is a risk-based capital measure used to assess whether a bank has enough capital relative to the risks it takes.
Capital helps a bank absorb losses and continue operating during stress. Risk-weighted assets adjust the bank's assets and exposures for regulatory risk, so riskier activities generally require more capital.
Key Takeaways
- CAR compares bank capital with risk-weighted assets.
- It is a risk-based measure of bank capital strength.
- Higher capital ratios generally mean more loss-absorbing capacity.
- Regulators use several capital ratios, not just one CAR measure.
- CAR should be read with asset quality, liquidity, earnings, and stress-test context.
How the Capital Adequacy Ratio Works
A simplified CAR formula is:
Regulatory capital is the capital recognized under bank capital rules, often divided into tiers such as common equity tier 1, tier 1, and total capital. Risk-weighted assets are exposures adjusted for regulatory risk weights.
If a bank has $12 billion of regulatory capital and $100 billion of risk-weighted assets, its simplified capital adequacy ratio is 12%.
Capital rules often include minimum ratios plus buffers. A bank can be above a basic minimum but still face restrictions or supervisory pressure if its capital cushion is too thin for its risk profile.
Capital Ratio Examples
Ratio | Numerator | Denominator |
|---|---|---|
Common equity tier 1 ratio | Highest-quality common equity capital | Risk-weighted assets |
Tier 1 capital ratio | Tier 1 capital | Risk-weighted assets |
Total capital ratio | Tier 1 plus eligible tier 2 capital | Risk-weighted assets |
Leverage ratio | Tier 1 capital | Average or total exposure measure |
Why It Matters
CAR matters because banks operate with leverage. Even modest loan losses can become serious if a bank has too little capital. Strong capital levels can support confidence, lending capacity, and resilience during economic stress.
Regulators use capital standards to reduce the risk that bank losses spill over to depositors, the deposit insurance fund, or the broader financial system.
Limits and Misunderstandings
A strong CAR does not guarantee a bank is safe. Capital ratios depend on asset quality, risk weights, model assumptions, accounting values, liquidity, interest-rate risk, and management decisions.
CAR is also not the same as cash. Bank capital is a balance-sheet cushion that absorbs losses; liquidity is the ability to meet cash outflows when they come due.
The Bottom Line
The capital adequacy ratio compares regulatory capital with risk-weighted assets. It is a core bank-safety measure, but it should be read with other capital, liquidity, earnings, and risk indicators.