The third quarter of 2026 showed how quickly the operating assumptions about a market can change. Equities entered July with momentum, carried by solid earnings and heavy AI investment. They exited September with oil sharply higher, yields at elevated levels not seen in over two decades, and a central bank tightening again.
July brought the first signs of strain. The fragile U.S.-Iran framework that closed the second quarter never took hold, and as disruptions mounted, Brent crude (the global benchmark for oil prices) climbed sharply from early-July lows. At its July 29 meeting, the Federal Reserve held rates steady, but three regional presidents dissented in favor of a quarter-point increase. Chairman Kevin Warsh declined to offer guidance, stressing only that the Committee "will not hesitate to act." Bond markets declined, lifting the 30-year Treasury yield to 5.2%, the highest since 2007.
Equities regained their footing in August on economic resilience and a strong close to earnings season, with broad gains across developed and emerging markets. Energy prices offered brief relief as Brent crude dipped below $80 a barrel on hopes for progress in Iran talks, then rebounded above $90. Underneath that rebound, supply conditions tightened, and European natural gas prices jumped more than 30% to the highest level since 2022. At the Fed's annual Jackson Hole symposium, sentiment shifted as Warsh warned that cooler inflation readings were not yet proof of a sustained improvement.
September delivered the rate hike markets had begun to expect, along with several other shocks. Crude surged to its highest level of the year as production in the Persian Gulf fell further and attacks disrupted the Red Sea route bypassing the Strait of Hormuz. Diesel crossed $6 a gallon for the first time, and the 10-year Treasury yield topped 5%. AI took center stage as warnings from leading labs prompted an industry-wide call to slow development. On September 16, the Federal Open Market Committee (FOMC) unanimously raised the federal funds target range by a quarter point to 3.75%–4.00%, its first increase since July 2023. In Warsh’s words: “The plain fact is that inflation is too high and has been for too long.” The European Central Bank and Bank of Japan also tightened. Chinese President Xi Jinping's state visit to Washington closed the quarter with a two-month trade truce extension, a positive development but shorter than many economists had anticipated.
The quarter ultimately marked a meaningful shift in the market's operating backdrop. Resilient growth and AI-driven earnings still supported gains, but rising energy prices renewed inflation pressures, and the Fed raised rates for the first time in three years. Oil prices continued to fluctuate with news from the Middle East in the quarter’s final days, as the outcome of diplomatic talks remained uncertain.
U.S. equities, as measured by the Russell 3000 Index, advanced moderately during the third quarter, though the headline result concealed one of the widest gaps between market segments in recent memory. Higher rates and energy costs weighed on companies with greater financing needs and thinner margins, while the largest technology and AI-linked companies, backed by strong profitability, kept attracting capital. By quarter-end, large-cap stocks (S&P 500) led by a wide margin and were the only segment to finish positive, followed by mid-cap (S&P MidCap 400) and small-cap (S&P SmallCap 600), with a 10.2% return gap between the largest and smallest.
Factors are well-established drivers of risk and return, rooted in economic theory and observed across markets and time periods. Leadership shifted in the third quarter, as growth and value finished higher, while momentum and quality declined. Value led most of the quarter, supported by energy exposure, before fading in September as growth pulled ahead on renewed confidence in AI’s long-term prospects. Momentum, the second quarter's leader, declined as selloffs in July and September weighed heavily on the market's most popular stocks, though it regained some ground late in the quarter. Quality finished last, as a strong economy and rising rates rewarded growth potential more than earnings stability and balance-sheet strength.
Source: Planning Alternatives, YCharts data
International equities (MSCI ACWI ex-U.S.) posted modest gains, trailing U.S. large-cap stocks but outperforming domestic mid- and small-caps. Abroad, tighter monetary policy and higher oil prices weighed most on energy-importing economies. Developed markets (MSCI EAFE) outperformed emerging markets (MSCI Emerging Markets), flipping the prior quarter's leadership, as a stable U.S. dollar offered little of last quarter's currency support. Emerging markets finished slightly lower after semiconductor-heavy markets fell sharply in July's technology selloff before recovering most of those losses by quarter-end. The quarter reinforced the value of broadly diversified international exposure, as regional leadership can shift quickly and unpredictably.
Fixed income declined in the third quarter as persistent inflation, stronger-than-expected economic data, mounting concern over federal deficits, and a more hawkish Fed pushed yields higher across the curve. The Bloomberg U.S. Aggregate Index finished lower. Bonds sold off through July as three Fed officials dissented in favor of a rate increase and long-term yields climbed to their highest levels in almost 20 years. A partial recovery followed in August before markets turned lower in late September, when the Fed's rate increase, elevated energy prices, and strong business activity data drove yields to quarterly highs.
Performance varied meaningfully by duration. Shorter-duration bonds (Bloomberg U.S. Government/Credit 1-3 Year Index) held up best, declining less than 1%, as lower rate sensitivity limited price losses and higher starting yields provided an income cushion. Municipal bonds (Bloomberg Municipal Bond 1-10 Year Blend) lagged most, a sharp turn from their prior-quarter lead, as rate sensitivity and heavy supply weighed on the sector.
The Treasury curve remained positively sloped and shifted higher across every maturity, with intermediate maturities rising most. Weak demand at a late-September five-year note auction added to the pressure, signaling that investors are requiring higher yields to absorb heavy government borrowing. The 30-year yield ended the period above 5.5%, its highest level since 2002. Higher yields raised borrowing costs and pushed down prices of existing bonds, but newly issued Treasuries now offer some of the highest yields in roughly two decades. For long-term investors, reinvesting interest and maturing bonds at these higher rates can increase future income.
Source: Planning Alternatives, Treasury.gov data
Alternative assets delivered mixed results during the third quarter, reflecting a sharp reversal in commodity and real asset markets. Commodities led all major asset classes by a wide margin, as disruptions to Middle East production and shipping tightened supply and drove energy prices higher. Gains extended beyond energy, with precious and industrial metals advancing amid persistent inflation. Natural resource equities followed, trailing commodities, as both gave back some gains late in the quarter when oil eased.
By contrast, global real estate (S&P Global REIT Index) declined, reversing its standing from the prior quarter. Interest rates were the primary headwind. As yields rose and central banks tightened, borrowing costs increased and bonds began offering income competing more directly with what real estate provides. The quarter was a useful reminder that real assets do not always move together: commodities tend to benefit when supply is disrupted and prices rise, while real estate is more sensitive to interest rates because it relies on financing.
Source: Planning Alternatives, YCharts data
Source: Planning Alternatives, YCharts data
“Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less.”– Marie Curie
Researchers and executives at the world's leading AI companies issued an urgent warning during the third quarter: the technology they are building could pose an existential risk. They called on their own industry to slow down. Markets reacted swiftly, with AI-linked stocks selling off before recovering within days. The episode raised a reasonable question: how should an investor’s portfolio respond to a risk of that magnitude?
History offers useful context. As the chart below illustrates, the S&P 500 has advanced through the Machine Age, the Atomic Age, the Space Age, the Personal Computer Revolution, and the Internet Era. Nearly every one of those transitions arrived with credible warnings attached. Nuclear fission, first harnessed in 1942, raised genuine fears about human survival, and the scientists who developed it were among the first to sound the alarm. The market did not ignore those concerns. It absorbed them, repriced along the way, and compounded over decades. AI now sits at the chart's right edge.
Note: The S&P 500 index launched in 1957, performance prior to 1957 incorporates the performance of the predecessor index, the S&P 90 index.
This does not mean the current warnings are unfounded. The point is narrower: transformative technologies have consistently arrived alongside uncertainty, and long-term investors have been rewarded for participating in the growth they produced rather than waiting for the questions to be settled.
Looking ahead, those questions extend beyond AI. Many of the forces that shaped the quarter are still in motion, and November's midterm elections add another variable. In this environment, the discipline remains the same: diversify across drivers of return, stay invested when the path looks unclear, and remember that durable outcomes have come from time in the market rather than certainty about it.
Portfolio positioning evolved during the third quarter through strategic, targeted adjustments to our bond portfolios. The intermediate core anchors remain as the foundation, with the new positions allowing for more dynamic access across the curve and credit-quality spectrum where investors may be better compensated.
These decisions reflect our ongoing research process, which evaluates strategies across market cycles, studies how holdings perform and interact, and incorporates third-party research to form a consensus view. That process is designed to identify structural shifts in the market environment and adapt as they emerge.
Our focus remains on disciplined, research-driven decision-making rather than reacting to short-term developments. Strategic asset allocation, diversification, and a long-term perspective guide our process, keeping portfolios positioned to capture opportunity and manage changing conditions in pursuit of True Wealth.
Planning Alternatives is an investment advisory firm registered with the Securities and Exchange Commission (“SEC”). SEC registration does not imply a certain level of skill and or expertise. The information presented should not be construed as personalized investment, financial, legal or tax advice. It is limited to general information about our views on the economy, various investment options, and investment strategies. Planning Alternatives does not provide tax, legal or accounting advice. Before implementing any approaches presented you should consult your own tax, legal and accounting advisors before engaging in any transaction about the financial, legal and tax suitability for you.
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