Credit glossary

What is an OAS (Option-Adjusted Spread)?

A spread measure that accounts for embedded options (e.g., call features) in a bond's structure.

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Definition

OAS (Option-Adjusted Spread)

A spread measure that accounts for embedded options (e.g., call features) in a bond's structure.

Example

How it works in practice

A cat bond includes a provision allowing a six-month maturity extension if a trigger event is being assessed. This extension feature is economically similar to an embedded option. The OAS adjusts for the value of this optionality, giving investors a cleaner measure of the pure risk premium than the raw spread. Two bonds with the same nominal spread but different extension provisions will have different OAS values.

Related terms

Related glossary entries

Z-SpreadCredit AT1 (Additional Tier 1)Credit CoCo (Contingent Convertible)Credit Coupon DeferralCredit Hybrid CapitalCredit NotchingCredit

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A

Aggregation RiskCyber ARC (African Risk Capacity)ILS AT1 (Additional Tier 1)Credit Attachment PointILS

B

Basis RiskILS Binary TriggerILS

C

Calculation AgentILS Cat BondILS Catastrophe ModelRisk Modelling CCRIF (Caribbean Catastrophe Risk Insurance Facility)ILS CedantReinsurance CoCo (Contingent Convertible)Credit CollateralILS Collateralised ReinsuranceILS Conditional Expected Loss (CEL)ILS CorrelationILS CouponILS Coupon DeferralCredit Cyber Cat BondCyber

D

DDoS AttackCyber DiversificationILS Due DiligenceILS

E

ESGILS Exhaustion PointILS Expected Loss (EL)ILS Expense LoadILS ExposureGeneral Insurance Extension RiskILS

G

GDPRCyber Green Cat BondILS

H

Hazard ModuleRisk Modelling HIM SeasonILS Hybrid CapitalCredit

I

IBRD (International Bank for Reconstruction and Development)ILS ILW (Industry Loss Warranty)Reinsurance Indemnity TriggerILS Industry Loss Index TriggerILS

L

Loss Exceedance CurveRisk Modelling

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N

Net Risk Multiple (NRM)ILS New Issue ConcessionILS NIST CSFCyber NotchingCredit

O

OAS (Option-Adjusted Spread)Credit Offering CircularILS

P

Parametric TriggerILS PCS (Property Claims Services)ILS Peak PerilILS PerilGeneral Insurance PERILS AGILS PremiumGeneral Insurance Probability of First Loss (PFL)ILS Probable Maximum Loss (PML)Risk Modelling Proportional PayoutILS

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RansomwareCyber Reg SILS ReinsuranceReinsurance Resilience BondILS RetrocessionReinsurance Return PeriodRisk Modelling Risk LoadILS Risk-Free RateCredit RoadshowILS RT1 (Restricted Tier 1)Credit Rule 144AILS

S

SCR (Solvency Capital Requirement)General Insurance SeasonalityILS Secondary MarketILS Sharpe RatioILS SidecarILS Silent CyberCyber SOFRILS Solvency IIGeneral Insurance Special Purpose Vehicle (SPV)ILS SpreadILS Structuring AgentILS Subordinated DebtCredit Supply Chain AttackCyber

T

Tier 2 CapitalCredit Total Return SwapILS TrancheILS

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Vulnerability ModuleRisk Modelling

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Wang TransformRisk Modelling War ExclusionCyber Write-DownCredit

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