Stock Markets May 18, 2026 12:53 PM

Longer-dated Treasury Yields Surge to 14-Month High as Oil Prices Rise on Iran Conflict

10-year and 30-year Treasury yields spike overnight on inflation concerns tied to disruptions near the Strait of Hormuz

By Ajmal Hussain CL

Yields on longer-dated U.S. Treasury notes climbed to their highest levels in more than a year during overnight trading before easing back, driven by inflation concerns after crude oil topped $111 a barrel amid stalled negotiations in the Iran conflict and incidents around the Strait of Hormuz. The 10-year yield peaked at 4.631% and later eased to 4.585%, while the 30-year yield settled around 5.125% after also touching year-plus highs.

Longer-dated Treasury Yields Surge to 14-Month High as Oil Prices Rise on Iran Conflict
CL

Key Points

  • The 10-year Treasury yield rose to 4.631% in overnight trading, the highest level since February 2025, and later eased to 4.585%.
  • The 30-year Treasury yield also touched its highest point in over a year before settling down just over 2 basis points at 5.125%.
  • Rising crude oil—above $111 per barrel—and stalled Iran negotiations, alongside ship attacks and seizures near the Strait of Hormuz, intensified inflation concerns and pressured global bond markets. Sectors affected include fixed income, energy, and maritime transport.

Yields on longer-dated U.S. Treasury securities pushed to their strongest levels in over a year during overnight trading on Monday, then pulled back slightly as markets digested renewed inflation risks tied to the ongoing Iran conflict.

The benchmark 10-year Treasury note climbed to 4.631% in overnight trading, its highest reading since February 2025. The yield later retreated and was last reported down modestly at 4.585%.

The 30-year Treasury bond followed a similar intraday trajectory, trading at the highest levels seen in more than a year before easing. It was last down a little more than 2 basis points at 5.125%.

Market participants pointed to intensifying inflation concerns after crude oil prices pushed above $111 per barrel last week. Those gains in oil coincided with limited progress in negotiations surrounding the Iran war and a series of ship attacks and seizures in and around the Strait of Hormuz, a key artery for global oil shipments.

The sudden move in fixed income came after crude topped the $111 mark and a public warning from President Donald Trump on Truth Social telling Iran to "better get moving" on the latest U.S. peace proposal. The combination of higher oil prices and elevated geopolitical risk helped drive a sharp sell-off in global bond markets on Monday.

Investors grappled with the inflation implications of a higher oil price environment and the potential for further supply disruption in a critical shipping corridor. That concern was reflected in both the 10-year and 30-year yields reaching their peak readings for the first time in more than a year before modestly easing.

Overall, the trading session highlighted how developments in energy markets and geopolitics can quickly feed into fixed-income repricing when inflation expectations shift. For now, yields remain elevated relative to recent levels following the overnight bout of selling pressure.

Risks

  • Further escalation in the Iran conflict or additional incidents around the Strait of Hormuz could push oil prices higher, increasing inflationary pressure and driving bond yields up - this would impact fixed-income markets and the energy sector.
  • Sustained elevated oil prices may keep inflation expectations elevated, which could lead to continued volatility in the Treasury market and weigh on interest-sensitive assets - affecting bonds and sectors reliant on accommodative rates.
  • Disruptions to shipping in a vital oil transit route could exacerbate supply concerns and add upward pressure to energy prices, creating additional market uncertainty for commodities and global trade-linked industries.

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