Demand for long-term corporate bonds surges as issuance remains scarce

Investor demand for long-duration U.S. investment-grade corporate bonds is significantly exceeding available supply.
Aon's 30-year notes reportedly attracted orders worth roughly five times the amount offered, while GSK's deal drew demand of about 10 times its size. Despite that appetite, only around 5% of U.S. investment-grade bonds issued in early September had maturities of 30 years or longer, the smallest share since 2020.
With 30-year borrowing costs near their highest levels since the Global Financial Crisis, companies have little incentive to lock in today's rates if they expect financing conditions to improve. That leaves pensions and insurers with fewer long-duration assets available to match their long-term liabilities.