When-Issued Trading
When-issued trading refers to the forward market in newly announced Treasury securities that begins after the Treasury announces an upcoming auction and continues until the securities are actually issued and settle, allowing participants to trade the anticipated securities before they formally exist.
When a Treasury auction is announced — typically several days before the auction date — a when-issued (WI) market immediately opens in the secondary market. Participants can buy or sell the not-yet-existing Treasury securities on a forward basis, with settlement deferred until the issue date. When-issued transactions are quoted on a yield basis and serve as the market's real-time estimate of where the new security will clear at auction.
For a 10-year Treasury note, the when-issued market opens roughly one week before the auction and runs through the auction date and into the settlement date, which is typically one business day after the auction for notes and bonds. Prior to the auction, when-issued yields reflect the market's best estimate of the auction clearing yield given current supply, demand, and macro conditions. The spread between the when-issued yield and the prevailing on-the-run yield provides a signal about whether the new security is expected to price through or concede to the existing benchmark.
Primary dealers and other sophisticated market participants use when-issued trading for several purposes. Dealers routinely sell when-issued securities short ahead of an auction — a practice known as building a short — as a way to pre-hedge the inventory they expect to win at auction. If a dealer expects to be awarded $500 million at the upcoming 10-year auction, selling $500 million of when-issued 10-year notes short before the auction locks in an effective sale price. After the auction settles and the dealer receives the physical securities, the short is covered naturally.
The auction tail — the difference between the final stop-out rate and the pre-auction when-issued yield — is the primary post-auction diagnostic metric. A stop-out yield that is higher than the pre-auction when-issued yield by more than a few tenths of a basis point is called a tail and indicates that the auction required a price concession to clear, suggesting weaker demand. A stop-out yield at or through the when-issued level indicates strong demand and is called an in-the-cover or through result.
For fixed income traders, the when-issued market serves as the most accurate real-time indicator of expected auction clearing levels and is closely watched in the hours before an auction deadline. Significant movements in when-issued yields during the blackout window — when primary dealers are constrained from communicating with customers — can signal large directional positioning by the dealer community.