Stocks and Bonds Are Moving Together — and That Could Reshape Your Portfolio
LPL Research Chief Investment Officer Marc Zabicki is focused on a quiet but important shift in financial markets: stocks and bonds are starting to move in the same direction more often. That matters because the whole logic behind the classic 60/40 portfolio — 60% stocks, 40% bonds — depends on the two asset classes moving independently, or even in opposite directions. Zabicki's analysis, published in LPL's "Managing Around a Changing Market" edition, looks at how the stock-bond correlation has shifted and what it means for how investors build diversified portfolios.
The backdrop is a bond market under pressure. Long-term Treasury yields (the interest rate the U.S. government pays to borrow for decades) have climbed for months, pushing the 30-year bond to levels not seen since the mid-2000s. By late July 2026, the 30-year Treasury yield reached its highest level since that era, with the benchmark yield hitting 4.747% on July 31 as investor concerns drove a sell-off in bonds that pushed yields to multi-year highs. Reuters
That July spike followed a volatile spring. On May 20, 2026, the 10-year Treasury note yield dropped 9.4 basis points (one basis point equals one-hundredth of a percentage point) to 4.576% after having risen to multiyear highs — a sharp intraday reversal. Reuters LPL's weekly market commentary in late October 2025 had already flagged technical deterioration in the long bond, noting the 30-year yield had broken below key levels and identifying 4.42% and 4.30% as major support zones — price levels where buyers had historically stepped in. LPL Research
In a December 2025 piece, LPL Research explored how a potential Federal Reserve leadership change and accompanying policy shift could affect interest rates and the stock-bond correlation, with implications for portfolio strategy. LPL Research The firm also examined the fixed-income allocation question more broadly, arguing in April 2026 commentary that global bonds are broadening their yield offerings and reducing U.S. concentration, creating diversified income opportunities in what LPL called a "multi-polar world." LPL Research
Stocks, for their part, have largely ignored the bond market's turbulence. The Dow Jones Industrial Average closed above 49,000 in a record-setting start to 2026, with the S&P 500 notching a concurrent record high on January 6. Yahoo Finance The S&P 500 went on to log its eighth straight weekly gain by late May. CNN Business By early June, world equities were back near or at record highs. Reuters And on August 13, 2026, the S&P 500 closed at another record high, rising 50.49 points, or 0.65%, on a session where Treasury yields and oil prices both fell. WSJ
The tension between rising long-term yields and relentlessly climbing stocks is the core of what Zabicki is addressing. Think of diversification as a shock absorber: when stocks hit a pothole, bonds have historically smoothed the ride because they tended to move the other way. During the post-2008 era of low inflation and ultra-low interest rates, that relationship was reliable — equities sold off, Treasuries rallied, and the 60/40 portfolio absorbed the blow. But when both asset classes sell off together, as happened during the 2022 downturn, that shock absorber stops working.
The 30-year yield's dip to 5.07% on June 2, 2026 — down 3 basis points on a session where the S&P 500 and Nasdaq Composite each climbed 0.6% — shows the intermittent relief rallies that have broken up the broader trend. MarketWatch But the longer arc, from the September 2025 sell-off when global stocks fell and European long-dated yields hit multiyear highs, through the May 2026 reversal and the July spike to 4.747%, points to a bond market repricing that has not yet derailed the equity rally. Reuters
The broader context here is whether this correlation shift is permanent or cyclical. If stocks and bonds have durably moved into positive correlation — meaning they rise and fall together — then holding bonds for their hedging value (what portfolio managers call "duration exposure") may need a rethink. The case for spreading fixed-income holdings beyond U.S. Treasuries into global government and corporate bonds, as LPL's April commentary suggests, becomes less about chasing yield and more about genuine structural diversification. The S&P 500's record close on August 13, which came alongside falling yields, is a reminder that the correlation is not fixed; it shifts with the inflation and growth environment. But long-term yields hovering near multi-decade highs while stocks sit at records is itself the regime change worth watching.
