For investors watching the stock market, one of the biggest signals may not be coming from stocks at all.
It’s coming from the bond market.
Long-term US Treasury yields have been climbing, and BNP Paribas believes that pressure could continue in the months ahead. The bank expects the yield on the 30-year Treasury bond to reach 5.6%, compared with about 5.43% as of Thursday afternoon.
That matters because higher bond yields can change the equation investors use when deciding where to put their money.
When Treasury yields rise, bond prices generally move lower. At the same time, higher Treasury yields can make stocks look less attractive because investors can compare the relatively low-risk returns available from government bonds with the potential long-term earnings from equities.
And BNP Paribas believes several forces could push those yields even higher.
The 5.6% Question
The 30-year Treasury yield has already moved significantly higher this year.
According to the information provided, it stood at 4.83% at the beginning of 2026 and had climbed to 5.43% by Thursday afternoon.
BNP Paribas expects another move higher, forecasting a potential rise to 5.6% in the months ahead.
The bank’s concern is centered largely on the growing cost and scale of US government borrowing.
But this isn’t happening in isolation.
Higher oil prices have added to inflation concerns, while the government’s growing debt needs and strong borrowing demand from both the government and large AI companies have also contributed to pressure in the bond market.
The result is a situation where several different forces are pushing in the same direction.
Three Forces Could Push Yields Higher
BNP Paribas identified three developments that could intensify concerns surrounding US government finances and potentially put additional upward pressure on long-term yields.
1. Higher Rates Could Increase the Government’s Interest Bill
The first factor is monetary policy.
The Federal Reserve raised interest rates by 25 basis points in September, and the market was expecting potentially two additional increases during 2026, followed by another increase by April 2027.
Higher short-term rates can have an important consequence for the US government’s finances.
Because the Treasury conducts much of its borrowing toward the shorter end of the yield curve, higher rates can increase the government’s interest expenses as debt is refinanced or newly issued.
BNP Paribas estimates that if the four rate increases priced into the market were delivered, the Treasury’s interest burden could rise by approximately $116 billion during the first year.
By the second year, the increase could reach roughly $168 billion.
That is a substantial number.
BNP strategist Guneet Dhingra put the figure into perspective by noting that a $168 billion increase in interest expenses would effectively eliminate all of the additional tariff revenue collected in 2025.
In other words, higher interest costs could absorb a significant amount of government revenue.
2. The Budget Deficit Is Widening Again
The second concern is the US budget deficit.
According to BNP Paribas, the deficit is beginning to expand again, with several factors contributing to the deterioration.
Tariff rollbacks and refunds are part of the picture, while higher long-term interest rates are also increasing the government’s financing costs.
That creates the possibility of a feedback loop.
Higher yields increase borrowing costs. Higher borrowing costs can add to government spending. Greater fiscal pressure can then increase investor concerns about government debt, potentially putting further pressure on yields.
The cycle is important because the bond market is highly sensitive to expectations surrounding government borrowing and future debt levels.
3. Spending Could Remain High After the Midterms
The third issue involves what happens to government spending after the US midterm elections.
BNP Paribas argues that investors could be underestimating the government’s willingness to continue spending after the election.
One possible scenario involves Democrats regaining control of the House of Representatives, or potentially both chambers of Congress.
Investors might assume that a divided government would lead to less spending because of greater disagreement between Congress and the executive branch.
But BNP Paribas points to what happened following the 2018 midterm elections as an example suggesting that spending can remain elevated even under those circumstances.
Defense spending adds another layer to the discussion.
The bipartisan Senate Armed Services Committee has already approved a proposed $250 billion increase in the defense budget, according to the information provided.
That potential increase in spending adds to the fiscal pressures BNP Paribas is watching.
Why Does This Matter for Stocks?
The bond market and stock market may appear to operate separately, but long-term Treasury yields can influence how investors value equities.
Think of Treasury yields as a benchmark.
When yields are relatively low, investors may be more willing to accept the uncertainty of stocks in pursuit of potentially higher long-term returns.
But as Treasury yields climb, the calculation changes.
Investors can compare the potential earnings generated by stocks with the returns available from government bonds. Higher Treasury yields can therefore increase the return investors may demand from stocks to justify taking on additional risk.
That can put pressure on stock valuations, particularly when long-term yields rise quickly.
This is why a move in the 30-year Treasury yield can attract attention well beyond the bond market itself.
Oil, Inflation and AI Are Also Part of the Picture
The pressure on yields isn’t coming exclusively from government debt concerns.
Rising oil prices have renewed concerns about inflation, which can influence expectations for interest rates and bond yields.
At the same time, borrowing demand isn’t limited to Washington.
Large AI companies and hyperscalers are also seeking substantial amounts of capital as they invest in the infrastructure needed to expand their businesses.
That additional demand for borrowing is another piece of the broader market environment.
Together, inflation concerns, government financing needs and corporate borrowing demand are creating a complicated backdrop for long-term Treasury yields.
The Bond Market’s Next Test
The key question now is whether the rise in long-term yields has further to go.
BNP Paribas believes it does.
Its 5.6% forecast for the 30-year Treasury yield reflects concerns about government debt, interest costs and future fiscal spending rather than one isolated economic development.
If yields continue climbing, investors may have to keep reassessing the relationship between bonds and stocks.
For the moment, the important signal is coming from the long end of the Treasury market.
And with several fiscal and monetary forces moving at once, the next move in bond yields could matter far beyond Wall Street’s bond desks.
