Counterparty Credit Limit

A counterparty credit limit is an internal ceiling a bank, broker, asset manager or corporate treasury sets on the amount it could lose if a specific counterparty failed to perform. It covers trading, lending and payment relationships and is usually approved by an independent credit risk function rather than by the business lines that want to deal. Exposures are measured against the limit continuously, and new trades that would breach it are blocked or need special approval.

Counterparty credit limits are the main everyday tool for managing counterparty risk. They are different from a credit cap, which is set by a payment system or settlement agent to limit how much credit a participant can use within that system. They also differ from a consumer credit limit on a card or loan, which caps how much a customer may borrow, and from regulatory large exposure limits, which set an outer boundary in law.

A shopkeeper who lets regular customers buy on credit keeps a notebook with a maximum next to each name. A long-standing customer with a steady job might be allowed to run up a large tab; a new face only a small one. Once a customer reaches the limit, no more goods leave the shop until something is paid back.

A counterparty credit limit is the number next to each name in a bank's notebook. It reflects how far the bank trusts that counterparty and how much it could afford to lose, and it stops eager traders from piling up too much risk with one firm.

Banks usually break the overall limit for a counterparty into sub-limits that match different kinds of exposure:

• Pre-settlement limits. These cover the cost of replacing trades such as forwards, swaps and options if the counterparty defaults before settlement, the risk known as replacement cost risk.
• Settlement limits. These cap the amount that could be lost on a settlement date if the bank pays and the counterparty does not, which is principal risk. They are especially important in FX, where Herstatt risk arises from time-zone gaps.
• Money market and lending limits. These cover deposits placed with, and loans to, the counterparty.
• Daylight or intraday limits. These cap the amount of intraday credit extended, for example when a correspondent bank lets a client overdraw during the day.
• Tenor and product limits. These restrict the maturity or type of transaction allowed with a counterparty.

Lending usage is simple: the amount lent. For derivatives and other contracts whose value moves, banks estimate both current exposure, the mark-to-market value if positive, and potential future exposure, the amount the value could reach over the life of the trade at a high confidence level. Legally enforceable close-out netting lets the bank measure exposure on a net basis across trades, and collateral held reduces it further, after haircuts. Limits are usually set per legal entity and aggregated across the counterparty's corporate group, since affiliated firms can fail together.

Credit analysts assess each counterparty's financial strength, ratings, ownership and country, and propose limits that a credit committee approves. Limits are reviewed at least annually and cut quickly if the counterparty's condition worsens. Front-office systems check available headroom before a trade is executed. Excesses are reported and must be explained, approved or reduced.

Concentrated exposures matter beyond the single counterparty. The Basel large exposures framework, developed by the Basel Committee on Banking Supervision, generally limits a bank's exposure to a single counterparty or group of connected counterparties to 25% of its Tier 1 capital, with a tighter limit between the largest global banks. Internal limits are normally set well inside these legal ceilings.

In some deferred net settlement systems, participants set bilateral limits on the net amount they are willing to receive from each other before settlement, which is a counterparty credit limit applied inside the system. When banks move to payment versus payment settlement or to a central counterparty, their exposure shifts from many bilateral counterparties to a single infrastructure, which changes how limits are used but does not remove the need for them.

Limits depend on models and judgement. Potential future exposure estimates can understate risk in volatile markets, and wrong-way risk, where exposure rises as the counterparty weakens, is hard to capture. Limits also say nothing about loss once a default happens; they need to be paired with collateral, netting and sound legal documentation.