How Can a Safe U.S. Treasury Bond Help Bring Down a Bank?
U.S. government bonds are considered among the safest investments in the world. Yet falling bond prices helped bring down Silicon Valley Bank. How could that happen?
Imagine putting $1,000 into a bank.
You expect to get your money back whenever you need it.
Now imagine the bank takes some of its customers' deposits and buys government bonds.
That sounds reasonable.
The bonds are issued by the U.S. government, which has a long history of meeting its debt obligations.
But what happens if the bank needs to return customers' money before those bonds mature?
And what if the bonds are now worth less than the bank paid for them?
Suddenly, a seemingly safe investment can become a serious problem.
This is part of what happened to Silicon Valley Bank in March 2023.
The bank did not collapse because the U.S. government stopped paying its bonds.
It collapsed after rising interest rates, poorly managed financial risks and a rapid wave of withdrawals overwhelmed its ability to meet customers' demands.
The distinction matters.
An investment can be safe from default and still be dangerous when its owner needs to sell it.
Why Banks Buy Government Bonds
Banks do not simply place every customer's deposit in a vault.
They use deposits and other funding sources to make loans, purchase securities and support their operations.
They keep some assets readily available so customers can withdraw money.
Government bonds are attractive because they are generally easy to trade and have relatively low credit risk.
But there is an important difference between two questions.
Will the U.S. government make its promised payments?
And what price could the bank receive if it sells a bond today?
Those are not the same question.
A bond can continue making every promised payment while its market price falls.
To understand why, we need a simple example.
The $1,000 Bond That Became Less Attractive
Imagine buying a hypothetical government bond for $1,000.
It pays $30 in interest every year.
That is a 3% annual coupon based on its face value.
Now suppose newly issued bonds offer a 5% yield.
Why would another investor pay the same $1,000 for your older bond when a new investment offers a higher return?
They probably would not.
You may need to sell your bond for less than $1,000.
Its price falls until its remaining payments offer a return that is competitive with the market.
The exact price depends on the bond's remaining maturity, coupon payments and market yield.
But the basic rule is simple.
When market interest rates rise, existing fixed-rate bond prices generally fall.
The longer a bond's remaining maturity, the more sensitive its price can be to changes in interest rates.
This becomes important when a bank holds large amounts of long-term bonds.
Silicon Valley Bank Had a Lot of Long-Term Investments
Before its collapse, Silicon Valley Bank served many technology companies, startups and venture capital firms.
During the technology boom, customers deposited large amounts of money.
The bank grew rapidly.
According to the Federal Reserve's investigation, its assets increased from approximately $71 billion in 2019 to more than $211 billion in 2021.
SVB invested a significant portion of its deposits in longer-term securities, including U.S. Treasury bonds and government-agency mortgage-backed securities.
These were not all the same kind of investment.
But many shared a common vulnerability.
Their market values could fall when interest rates increased.
That is exactly what happened.
As the Federal Reserve raised interest rates in 2022, the value of many existing bonds declined.
Meanwhile, technology companies began using more of their cash as funding conditions became difficult.
SVB faced pressure from both sides.
Its investments were losing market value.
And its customers increasingly needed their deposits back.
Source: Federal Reserve — Review of Silicon Valley Bank
The Difference Between a Paper Loss and a Real Loss
Suppose a bank buys a bond for $1,000.
Later, its market price falls to $850.
If the bank can hold the bond until maturity and the issuer makes every promised payment, the bank may still receive the scheduled interest and principal.
But if the bank needs to sell immediately, it may receive only $850.
The $150 decline has now become a realized loss.
This is a simplified example. Actual bank accounting depends on how securities are classified, and a fall in market value can matter even before a sale.
The important point is that holding a bond until maturity requires something else.
Time.
A bank needs enough cash and stable funding to avoid selling investments at the wrong moment.
SVB did not have that flexibility when withdrawals accelerated.
A $1.8 Billion Loss Changed Everything
On March 8, 2023, Silicon Valley Bank announced that it had sold approximately $21 billion of available-for-sale securities.
The sale resulted in an after-tax loss of about $1.8 billion.
The bank also announced plans to raise approximately $2.25 billion in new capital.
Management intended to strengthen the bank's financial position.
But the announcement created a new problem.
Customers and investors became concerned about the bank's financial health.
Many of SVB's customers were connected through the same technology and venture capital networks.
News and concerns spread quickly.
The following day, depositors withdrew approximately $42 billion.
That was an extraordinary amount of money to leave a bank in a single day.
And the situation was getting worse.
SVB expected more than $100 billion in additional withdrawal requests on March 10.
The bank could not meet that demand.
California regulators closed Silicon Valley Bank on March 10, 2023, and appointed the Federal Deposit Insurance Corporation as receiver.
Source: FDIC — Lessons From the 2023 Regional Bank Failures
Why Did Customers Withdraw So Quickly?
There was another important detail.
Approximately 94% of SVB's deposits were uninsured at the end of 2022, according to the Federal Reserve.
In the United States, standard FDIC deposit insurance generally protects up to $250,000 per depositor, per insured bank, for each ownership category.
Many SVB customers were businesses holding much larger balances.
Some needed millions of dollars for payroll and operating expenses.
If they became worried about the bank, waiting could be risky.
So they tried to withdraw their money.
And when many customers tried to withdraw at once, the bank's liquidity problem became much worse.
This is called a bank run.
It does not necessarily begin because a bank has lost all its assets.
It can begin because too many people want their money back at the same time.
A bank can own valuable assets and still run out of money it can immediately use.
The Problem Was Bigger Than U.S. Treasury Bonds
It would be misleading to say that U.S. Treasury bonds alone destroyed Silicon Valley Bank.
The Federal Reserve's investigation identified several important failures.
SVB grew rapidly without adequately improving its risk management.
Its depositors were heavily concentrated in the technology sector.
Much of its funding consisted of large uninsured deposits.
Its investments were vulnerable to rising interest rates.
And its management failed to prepare effectively for a sudden loss of liquidity.
Federal Reserve supervisors also failed to respond sufficiently to risks that had been identified.
In other words, this was not simply a story about a bad investment.
It was a story about a bank whose assets and liabilities did not work well together when conditions changed.
The bonds were part of the problem.
But the failure came from the combination of falling asset values, unstable funding and inadequate risk management.
Source: Federal Reserve — SVB Supervisory Review, April 2023
Why Time Matters More Than People Think
Consider two people who own the same bond.
The first person does not need the money for ten years.
The second person needs the money tomorrow.
If the bond's market price falls, both investors experience the same change in market value.
But the consequences may be very different.
The first investor may be able to wait and collect scheduled payments.
The second investor may have to sell immediately.
Banks face a similar problem.
Customers can often withdraw deposits on demand.
But many loans and bonds held by banks cannot be converted into cash at their full expected value immediately.
This difference is called a maturity mismatch.
It is a normal feature of banking.
Banks often fund longer-term assets with shorter-term liabilities.
The danger comes when that mismatch becomes too large, poorly managed or dependent on customers who can all withdraw at once.
Does This Mean U.S. Government Bonds Are Unsafe?
Not in the same way that a financially weak company's debt may be unsafe.
U.S. Treasury securities are generally regarded as having very low credit risk.
But low credit risk does not mean zero investment risk.
There are different kinds of risk.
Credit risk: The issuer fails to make promised payments.
Interest-rate risk: The market value of a fixed-rate bond falls when yields rise.
Liquidity risk: The owner cannot obtain enough cash when needed without selling assets at unfavorable prices.
A U.S. Treasury bond may have low credit risk while still exposing its owner to interest-rate risk.
And if a bank has to sell a large amount of securities during a crisis, those market losses can become financially damaging.
The lesson is not that government bonds are inherently bad investments.
It is that the safety of an asset must be considered alongside how it is financed and when it may need to be sold.
Could Something Similar Happen Again?
The 2023 collapse led banks, regulators and investors to pay greater attention to interest-rate risk and deposit stability.
But the underlying economic problem has not disappeared.
When interest rates rise, older fixed-rate bonds can lose market value.
Banks may also face higher funding costs as depositors demand better returns.
The effects differ from bank to bank.
A well-capitalized bank with diversified deposits, adequate liquidity and effective risk management may handle these pressures.
A weaker institution may struggle.
The Federal Reserve's October 2026 discussion of supervisory reforms also shows that the lessons of SVB remain relevant.
Regulators continue to debate how bank risks should be identified and addressed before they become crises.
That does not mean another SVB-style collapse is inevitable.
It means the relationship between interest rates, bank assets and deposit funding deserves continued attention.
What Should Investors and Depositors Watch?
A bank's profits are important.
But they do not tell the entire story.
Investors can also examine how much of a bank's funding comes from uninsured deposits.
They can look at whether deposits are concentrated among similar customers or industries.
They can review unrealized losses on securities, the maturity of investments, available liquidity and capital strength.
And they can ask a simple question.
If many customers wanted their money tomorrow, could the bank meet those withdrawals without selling large amounts of assets at a loss?
No single number provides a complete answer.
But these questions help explain why two banks with similar investments can have very different levels of risk.
A Safe Asset Can Become Dangerous at the Wrong Time
Silicon Valley Bank's collapse revealed an uncomfortable truth about finance.
A bank can hold securities backed by the U.S. government and still fail.
Not because the government stopped paying.
Not because every asset suddenly became worthless.
But because the bank needed cash faster than it could safely obtain it.
Its long-term investments had lost market value.
Its customers wanted their money immediately.
And the bank was not prepared for the speed or scale of those withdrawals.
The same lesson extends beyond banks.
A business can own valuable property and still fail to pay its bills.
An investor can own a strong asset and still lose money by being forced to sell it.
A financial institution can appear wealthy on paper while struggling to find cash.
The value of an asset matters.
But so does the moment when its owner needs the money.
That is why a bond can be safe from default and still be dangerous to sell.
BEYOND THE OBVIOUS.
Sources
Federal Reserve — Review of the Supervision and Regulation of Silicon Valley Bank
FDIC — Lessons Learned From the U.S. Regional Bank Failures of 2023
U.S. Government Accountability Office — Review of the March 2023 Bank Failures
This article is intended for financial education and analysis. It is not a recommendation to buy or sell any security or deposit funds with any particular institution.