Execution Risk

Execution risk is the risk that a transaction, or a plan, is not carried out the way the parties intended. In trading it usually means the chance that an order is filled at a worse price than expected, only partly filled, or not filled at all. In payments and foreign exchange it also covers the danger that, in an exchange with two legs, one party delivers its side and the other does not. In business strategy the same phrase describes the risk that a sound plan fails because it is badly carried out.

Execution risk overlaps with several better-defined risk categories. It shades into settlement risk and counterparty risk when the problem is one side failing to deliver, into liquidity risk when the market is too thin to absorb an order, and into operational risk when systems or people make mistakes. It is not a separate regulatory capital category, but it is a practical concern for traders, payment firms and anyone exchanging value with a stranger.

Imagine agreeing to swap a bicycle for a neighbour's lawnmower. If you wheel the bicycle over first, you are relying on the neighbour to hand over the mower. If they refuse, or the mower turns out to be broken, the swap has gone wrong even though the deal itself was fair.

Trading has a similar problem with timing. You decide to buy at one price, but by the time your order reaches the market the price has moved, or there is no one willing to sell. In both cases the risk is not that the idea was bad, but that the deal was not completed as planned.

For traders and treasury desks, execution risk comes from the gap between deciding to trade and the trade actually completing. The main sources are:

• Price movement. Prices can change between the quote and the fill, producing slippage, especially in volatile or thinly traded markets.
• Depth. A large order can exhaust the best prices in the order book and fill at progressively worse levels.
• Rejection. In wholesale FX, some liquidity providers use a "last look" window and may reject a trade request after seeing it.
• Technology. Outages, delays and errors in electronic or algorithmic trading systems can leave orders unfilled or duplicated.

Firms manage these risks with limit orders, splitting large orders, routing across several providers through an FX aggregator, and best-execution policies. In payment businesses that convert currency after collecting customer funds, the time between quoting a customer and buying the currency creates the same exposure, and is often managed with hedging or by pre-buying currency.

When two parties swap one asset or currency for another, each leg may move through a different system. If those systems are not linked, one leg can complete while the other fails. The best-known example is the 1974 collapse of Bankhaus Herstatt in Germany, which was closed after receiving Deutsche Mark payments from counterparties but before paying out the matching US dollars; the episode gave its name to Herstatt risk.

The same problem appears in informal and peer-to-peer FX, where one person sends dollars to a bank account in one country and the other sends local currency to an account in another. Neither bank can see the other transfer, so the exchange cannot be made atomic, and someone must pay first. Even honest parties can be caught out by delayed, held or misdirected transfers, or by a bank recalling a payment.

Most controls either link the two legs or make failure costly for the party that defaults:

• Linked settlement. Payment versus payment ensures neither currency moves unless both do; Continuous Linked Settlement (CLS) applies this to wholesale FX.
• Central counterparties. A central counterparty (CCP) stands between buyer and seller and guarantees performance.
• Escrow. A neutral party, or a smart contract escrow, holds one side's funds until the other side performs; see also escrow in banking and payments.
• Atomic settlement. When both assets are on the same or linked ledgers, atomic swaps complete both legs or neither.
• Collateral and limits. Each party posts collateral that it forfeits on default, and trades are capped by an exposure limit; a proposed design of this kind is bilateral collateral escrow.

Outside markets, analysts use execution risk to describe the chance that a company fails to deliver a strategy, merger, product launch or technology migration, even if the plan is sound. Common causes are weak management capacity, underestimated complexity, regulatory delays and dependence on partners. In payments, expanding into many corridors or licences at once is often cited as a source of high execution risk, which is why firms tend to phase such expansion and set measurable targets for each step.

• CLS Group
• Global Foreign Exchange Committee: FX Global Code