Reader question: A trading-book bond may have modest day-to-day credit-spread sensitivity, yet it can lose a large amount almost instantly if its issuer defaults. How does Basel turn that discontinuous jump risk into a standardised market-risk capital charge?
The Basel standardised Default Risk Charge (DRC) separates default jump risk from ordinary spread sensitivity. The algorithm first converts each position into a gross jump-to-default (JTD) amount, using loss-given-default assumptions, notional or bond-equivalent exposure, and mark-to-market profit or loss already recognised. It then permits tightly constrained offsetting for long and short exposures to the same obligor, scales short-dated positions, groups net exposures into broad counterparty buckets, applies rating-based default risk weights, and limits hedge recognition with a Hedge Benefit Ratio (HBR).
The public computational chain is:
position economics → gross JTD → eligible same-obligor netting → maturity scaling → bucket + credit-quality weight → HBR-constrained short hedge benefit → DRC.
What this page owns — and what it does not
This page owns the Basel standardised DRC mechanism for non-securitisation trading-book exposures. It does not replace the banking-book standardised credit-risk algorithm, the ISDA CDS pricing/default-curve algorithm, the Basel large-exposure limit, or securitisation DRC. Those are separate owners.
This is public prudential mathematics and model education. It is not a trading recommendation, credit opinion, capital advice or personalized financial advice.
Why DRC is separate from ordinary credit-spread sensitivity
A spread-risk model asks what happens if credit spreads widen or tighten by prescribed amounts while the issuer continues to exist.
Default creates a different event: the instrument can jump discontinuously from a traded value to a recovery-dependent value. That gap is not well represented by a small continuous spread shock.
Basel therefore includes DRC as a distinct standardised market-risk component so banks cannot hedge away default tail risk merely by showing small local spread sensitivities.
Step 1: determine whether the position is long or short default risk
For DRC, “long” and “short” are defined by the economic result if the obligor defaults, not by the trading label of the instrument.
A long default-risk position is one that loses value on default. A short default-risk position gains value on default.
This matters for derivatives. A sold put on a bond is long default risk because issuer default hurts the option seller. A bought protection CDS is generally short the reference name’s default risk because default produces a protection payment.
Instrument direction is therefore payoff-based
The DRC engine should ask:
What is the position worth if the referenced obligor defaults now, compared with its current value?
It should not infer DRC direction from fields such as “buy/sell”, “payer/receiver” or “call/put” without evaluating the default payoff.
Step 2: compute gross jump-to-default separately for every exposure
Basel requires gross JTD to be calculated exposure by exposure before netting.
For ordinary non-securitisation debt and equity positions, the calculation uses:
- a supervisory LGD;
- the position’s notional or face value;
- cumulative mark-to-market P&L already recognised.
A useful stylised representation for a long position is:
Gross JTD ≈ LGD × Notional + P&L,
with signs handled under Basel’s long/short convention. The P&L term prevents the model from charging again for a loss already reflected in today’s market value.
Why mark-to-market P&L belongs in JTD
Suppose a senior bond has face value 100 but already trades at 70 because the issuer is distressed.
If a default model simply charges 75% LGD × 100 = 75 without recognising that 30 of value has already disappeared, it can double count deterioration already embedded in the bond price.
The Basel JTD construction therefore uses current market value/P&L to estimate the incremental jump from today’s marked value to the default state.
Supervisory LGD values
For non-securitisation DRC, Basel currently assigns:
| Exposure type | Supervisory LGD |
|---|---|
| Equity and non-senior debt | 100% |
| Senior debt | 75% |
| Covered bonds meeting the Basel definition | 25% |
These are standardised capital assumptions. They are not forecasts of the actual recovery on a specific future default.
Worked bond example
Assume a long senior bond:
- face value = 100;
- market value = 92;
- supervisory LGD = 75%.
The cumulative P&L is:
92 − 100 = −8.
A stylised gross JTD is therefore:
75 + (−8) = 67.
The intuition is that some credit loss is already recognised in the current mark. The remaining jump-to-default loss is smaller than 75.
Different instruments need bond-equivalent default exposure logic
A CDS, bond option or hybrid instrument does not always have a simple “face value minus recovery” payoff.
Basel therefore defines instrument-specific notional and P&L treatments. For a derivative whose legal terms eliminate default exposure on unwind, JTD can be zero. For options, the strike, option market value and default payoff can matter.
A production engine must use the instrument’s actual default-state economics rather than forcing every product into a plain-bond template.
Step 3: scale positions shorter than the one-year capital horizon
The DRC capital horizon is one year.
Positions with residual maturity shorter than one year receive prescribed maturity scaling for netting and exposure purposes. Basel currently floors the maturity used for this scaling at three months.
Conceptually:
Scaled JTD = Gross JTD × min(1, max(Maturity, 3 months) / 1 year).
A three-month position therefore receives roughly one-quarter of the one-year exposure scale, while a position longer than one year is not scaled above one.
Why short-dated protection cannot fully hedge long-dated default risk
Suppose a bank owns a five-year bond but buys a three-month CDS hedge.
The hedge protects only a fraction of the one-year capital horizon before it expires. Basel therefore does not allow that short-dated protection to offset the five-year exposure as if the maturities matched.
This prevents a bank from obtaining full capital relief with a hedge that disappears early in the risk horizon.
Derivative maturity means contract maturity, not underlying maturity
For maturity scaling and offsetting, the relevant derivative maturity is generally the maturity of the derivative contract itself.
A three-month option on a ten-year bond remains a three-month hedge for DRC purposes. Using the underlying bond’s ten-year maturity would overstate hedge persistence.
Step 4: offset only eligible exposures to the same obligor
Basel allows long and short JTD to offset only under restrictive conditions.
The exposures must reference the same obligor, and the short position must have the same or lower seniority relative to the long position so that it actually protects the relevant default loss layer.
This is economically sensible. A hedge on Company B should not offset Company A merely because both are in the same industry.
Seniority limits hedge recognition
A short equity exposure can offset a long bond exposure to the same obligor because equity is junior and is fully wiped out before senior debt in default.
But a short senior bond cannot necessarily offset a long equity exposure, because the senior instrument can retain recovery while equity goes to zero.
The DRC engine therefore needs the obligor and instrument seniority hierarchy.
Step 5: produce net long and net short JTD positions
After permitted same-obligor offsetting and maturity scaling, each obligor can leave:
- a net long JTD position;
- a net short JTD position;
- or zero residual default exposure.
Long and short residuals are then kept separately for bucket aggregation.
Step 6: assign one of three broad non-securitisation buckets
Basel defines three DRC buckets for non-securitisations:
- corporates;
- sovereigns;
- local governments and municipalities.
Hedging across these buckets is not recognised in the standardised DRC aggregation.
This means a short corporate credit position does not reduce a long sovereign DRC charge simply because the two happened to default together in a historical crisis.
Step 7: map credit quality to default risk weight
Basel’s current non-securitisation DRC weights are:
| Credit quality | Default risk weight |
|---|---|
| AAA | 0.5% |
| AA | 2% |
| A | 3% |
| BBB | 6% |
| BB | 15% |
| B | 30% |
| CCC | 50% |
| Unrated | 15% |
| Defaulted | 100% |
The weights rise sharply as credit quality deteriorates because a default jump becomes much more plausible over the capital horizon.
Ratings do not change gross JTD
Gross JTD measures the size of loss if default happens.
The risk weight reflects the credit-quality category used to scale that default exposure.
This separation is useful:
JTD severity × default-risk weight → weighted default exposure.
Two bonds with the same JTD but different ratings can therefore produce very different DRC.
Step 8: calculate the Hedge Benefit Ratio
Basel does not allow net short positions to offset risk-weighted longs one-for-one at bucket level.
For each bucket:
HBR = Σ Net JTDlong / [Σ Net JTDlong + Σ |Net JTDshort|].
The HBR uses unweighted JTD amounts.
If the bucket is mostly long default risk, HBR is near 1 and more short-hedge benefit is recognised. If the bucket contains a large amount of net shorts relative to longs, HBR falls and prevents excessive capital reduction.
HBR example
Suppose a corporate bucket has:
- total net long JTD = 120;
- total absolute net short JTD = 80.
Then:
HBR = 120 / (120 + 80) = 0.60.
Only 60% of the risk-weighted short side is then recognised in the bucket capital formula.
Why HBR exists
Without HBR, a bank could hold a large amount of low-quality long credit and a large short position in safer names inside the same bucket, then claim near-complete default-risk offset even though the hedge and exposure do not default together.
HBR restricts portfolio-level hedge benefit without pretending that broad-bucket shorts are perfect name-by-name hedges.
Step 9: calculate bucket DRC
For bucket b, Basel’s standardised formula is:
DRCb = max[ Σ(RW × Net JTD)long − HBR × Σ(RW × |Net JTD|)short, 0 ].
The zero floor means non-securitisation DRC for a bucket cannot become negative.
Total non-securitisation DRC is:
DRC = Σ DRCb
across the corporate, sovereign and local-government/municipality buckets. No hedging benefit is recognised between those buckets.
Worked bucket example
Assume a corporate bucket contains:
- BBB net long JTD = 100, RW = 6%;
- BB net long JTD = 20, RW = 15%;
- A net short JTD = 80, RW = 3%.
Unweighted totals:
Long JTD = 120.
Short JTD = 80.
HBR = 120 / 200 = 0.60.
Risk-weighted longs:
100 × 6% + 20 × 15% = 9.0.
Risk-weighted shorts:
80 × 3% = 2.4.
Bucket DRC:
max[9.0 − 0.60 × 2.4, 0] = 7.56.
The short hedge reduces capital, but not by the full 2.4.
Why a safer short can provide less capital relief than expected
In the example, the long book is BBB/BB while the short hedge is A-rated.
The A short receives only a 3% default weight, so its capital offset is smaller than an equal-notional short in a riskier rating band.
This makes sense: shorting a very safe issuer does not strongly hedge the jump-to-default risk of a weak issuer.
Unrated does not mean zero
Under the Basel table, unrated non-securitisation exposures receive a 15% DRC weight unless an allowed jurisdictional/internal-rating mapping applies with supervisory approval.
A missing external rating should therefore not silently produce zero capital.
Sovereign discretion is jurisdiction-sensitive
Basel contains specific discretion for certain sovereign and public-sector exposures under prescribed conditions.
A production implementation therefore needs:
- jurisdiction;
- currency of denomination/funding where relevant;
- counterparty class;
- current local implementation.
One global hard-coded sovereign weight table can be wrong.
DRC is not a probability-of-default model
The rating weights resemble increasing default likelihood, but DRC is a standardised capital framework rather than a calibrated one-year PD model.
A 6% DRC weight for BBB does not mean Basel predicts a 6% one-year default probability.
The weights are supervisory risk weights used inside the capital aggregation formula.
DRC is not the same as CDS expected loss
A CDS pricing model can use hazard rates, survival probabilities, recovery assumptions and discount factors to value expected premium and protection cash flows.
DRC instead measures regulatory jump-to-default capital under a fixed standardised framework. It uses supervisory LGD and rating weights and permits only specific hedging recognition.
This is why the existing CDS standard-model article and this page are complementary rather than duplicative.
DRC and large exposures answer different questions
A large-exposure rule asks:
How much of Tier 1 capital is concentrated in one counterparty or connected group?
DRC asks:
How much standardised market-risk capital should the trading book hold for default jump exposure?
A position can be well below the large-exposure limit and still generate material DRC.
Inputs and outputs
A robust non-securitisation DRC engine can require:
- instrument and position ID;
- obligor/reference entity;
- product type;
- long/short default-payoff direction;
- notional or bond-equivalent notional;
- current market value and cumulative P&L;
- seniority;
- covered-bond eligibility where relevant;
- residual contractual maturity;
- credit-quality category;
- corporate/sovereign/local-government bucket;
- jurisdictional rating and sovereign-treatment rules;
- Basel/local implementation version.
Outputs can include gross JTD, maturity-scaled JTD, net JTD by obligor, long/short totals by bucket, HBR, risk-weighted long and short amounts, bucket DRC, total DRC and diagnostic exceptions.
Evidence polarity: what supports confidence?
Evidence for a reliable DRC calculation includes instrument default payoffs that reconcile to valuation systems, bond-equivalent notionals that reproduce Basel examples, current market values and P&L, correct supervisory LGD by seniority, same-obligor netting only, maturity scaling that uses contract maturity, ratings mapped to the current table, and bucket DRC that can be independently recomputed.
Evidence against confidence includes long/short direction inferred mechanically from trade side, short protection netted across different obligors, five-year maturity assigned to a three-month option because its underlying bond matures in five years, missing P&L, unrated exposures given zero weight, or negative bucket DRC.
Counterexample: perfect spread hedge, imperfect default hedge
A bank can construct two credit positions whose small spread sensitivities offset almost exactly while their default payoffs differ materially.
The spread hedge may look neutral under ordinary delta risk, yet DRC remains because a jump-to-default event is discontinuous.
Counterexample: same obligor, wrong seniority
A short senior bond and a long subordinated bond reference the same company, but their recoveries in default can differ.
Basel therefore restricts offsetting by seniority instead of allowing all same-name notional to cancel.
Counterexample: same sector is not same obligor
A short investment-grade bank bond does not directly hedge the default of a different bank merely because both are financial institutions.
At bucket level HBR can recognise limited broad hedge benefit, but same-name netting is reserved for the same obligor under the rules.
Counterexample: lower rating can increase DRC without any position change
If a position is downgraded from BBB to BB, its DRC risk weight rises from 6% to 15% under the current table.
Notional and market value can be unchanged while regulatory default capital jumps because the credit-quality category changed.
Counterexample: a short hedge can reduce less capital when the book becomes more short
Adding more shorts reduces the HBR because the denominator grows. The incremental hedge benefit can therefore diminish.
This is intentional: the formula prevents a short-heavy bucket from creating large negative capital.
Weak links in implementation
Direction bug. Bought/sold flags replace default-payoff direction.
P&L sign bug. Existing mark-to-market loss is added instead of subtracted from remaining JTD.
LGD mapping error. Senior debt receives 100% instead of 75%, or a non-qualifying instrument receives covered-bond LGD.
Obligor-resolution error. Multiple identifiers for one issuer prevent valid netting.
Over-netting. Different obligors or prohibited seniority combinations are offset.
Maturity-source error. Underlying maturity replaces derivative contract maturity.
HBR weighting error. Risk-weighted JTD is used in HBR even though Basel uses unweighted net JTD totals.
Cross-bucket hedge leak. Corporate shorts reduce sovereign DRC.
Diagnostics: how to test the engine
- direction test: sold bond put should be long default risk under the Basel payoff logic.
- LGD test: equity/non-senior = 100%, senior debt = 75%, qualifying covered bond = 25%.
- market-value test: deteriorating bond price should change remaining gross JTD through P&L rather than double count the same loss.
- same-obligor test: eligible long and short positions in one name can net; different names cannot.
- seniority test: prohibit offsets that violate Basel’s seniority rule.
- three-month floor test: a one-month position should not scale below the prescribed minimum horizon.
- HBR identity test: with 120 long and 80 short unweighted JTD, HBR must equal 0.60.
- rating-table test: verify all nine current Basel weight categories.
- bucket-floor test: DRCb cannot become negative for non-securitisations.
- cross-bucket test: total DRC must equal the simple sum of the three non-securitisation bucket charges.
What would falsify confidence?
Confidence should be withdrawn if the engine cannot reproduce the current Basel MAR22 formulas; if JTD direction disagrees with default payoff; if same-name eligible hedges fail to net or different-name hedges do net; if maturity scaling uses the wrong contract horizon; if HBR is calculated from risk-weighted rather than unweighted JTD; if any non-securitisation bucket becomes negative; or if the final total does not equal the sum of bucket charges.
Alternatives and limits
Economic default-risk models can simulate hazard rates, recovery distributions, correlated defaults and stressed liquidity. Incremental default risk can also be estimated with Monte Carlo portfolio models. Those methods can be more granular than the Basel standardised DRC.
But they answer different questions. Standardised DRC is designed for regulatory comparability and robustness, using supervisory LGDs, rating weights, constrained netting and a fixed capital horizon. It deliberately sacrifices some model freedom.
How this connects to the surrounding knowledge estate
Default-event pricing and recovery assumptions connect to the ISDA CDS standard model. Banking-book credit capital uses the separate Basel credit-risk algorithm. Name concentration is constrained by the large-exposures framework. Total market and credit RWA ultimately feed the output-floor calculation.
Verification and update triggers
Preserve the Basel/local market-risk rule version, position snapshot, obligor map, seniority, contract maturity, market value, P&L, rating source, jurisdictional treatment and JTD calculation version. Revalidate after rating migration, restructuring, seniority change, instrument conversion, major model migration, regulatory implementation change or any reconciliation break between trading-book positions and reported DRC.
Primary and high-quality references
- Basel Committee on Banking Supervision, MAR22 — Standardised approach: default risk capital requirement, especially MAR22.9–22.26 for non-securitisations.
- Basel Committee, The Basel Framework, current consolidated edition accessed in 2026.
- Basel Committee, Minimum capital requirements for market risk, January 2019.
- Basel Committee, Minimum capital requirements for market risk — version with FAQs.
Educational boundary: This article explains Basel standardised trading-book default-risk capital mechanics. It does not determine a bank’s regulatory capital requirement, predict an issuer default or provide investment advice.