The crisis started with mortgages that banks knew borrowers could not afford to repay

In the years before 2008, banks began lending money for home purchases to people with poor credit histories, unstable jobs, or very little money saved for a down payment. These loans were called subprime mortgages. A bank would lend $300,000 to someone earning $35,000 a year, knowing the monthly payment would be half their income. The bank did this because it planned to sell the loan to another company when ready after closing — so if the borrower stopped paying, it was no longer the original bank's problem.

The banks that bought these loans bundled thousands of them together and sold pieces to investors around the world. A pension fund in Norway or a insurance company in Germany might own a slice of mortgages written in Arizona. This meant that when borrowers stopped paying — which happened in large numbers starting in 2006 — the losses spread everywhere at once. No one knew which banks or funds held the bad mortgages, so trust between banks froze solid.

Key Takeaways

  • Banks lent money for homes to people they knew could not afford the payments, then when ready sold those loans to other companies so they bore no risk.
  • These risky loans were bundled together and sold to investors worldwide, spreading the losses globally when borrowers stopped paying.
  • Banks stopped trusting each other because no one knew which institutions held the bad mortgages, and lending between banks nearly stopped.
  • When home prices fell, borrowers owed more than their houses were worth, and many walked away from their mortgages at the same time.
  • The crisis spread to regular bank accounts because banks that held deposits had invested heavily in these mortgage bundles and lost billions.

How banks profited without taking the risk

Before 2008, a bank's job was to take deposits from customers, lend that money to borrowers, and keep the risk if the borrower did not repay. If you defaulted on your mortgage, the bank that lent you the money lost it. This meant banks were careful about who they lent to.

Starting in the late 1990s, banks changed this model. A mortgage broker would originate a loan — write it and close it — then sell it within days to an investment bank. The investment bank would bundle hundreds of these mortgages together and sell pieces to pension funds, insurance companies, and other banks. The original lender had already made its fee and moved on. The investor who bought the bundle bore the risk.

This created a perverse incentive: the more loans a bank wrote, the more fees it earned, regardless of whether borrowers could actually repay. A loan officer had no reason to turn down a borrower with a stated income of $100,000 and a down payment of 2 percent, because the loan would be sold within a week. The risk belonged to someone else.

Why home prices falling triggered a cascade

For years, home prices rose steadily. A house bought for $200,000 in 2003 might be worth $350,000 by 2006. This rising value masked the problem: borrowers with bad credit were only staying current on their mortgages because they could refinance — take out a new, larger loan against the increased home value — and pocket the difference. When prices stopped rising in 2006, this stopped working.

As prices fell, borrowers found themselves underwater: they owed $300,000 on a house now worth $200,000. Walking away made financial sense. If you owe more than the house is worth and you lose your job, you stop paying. The bank forecloses, sells the house for $200,000, and eats the $100,000 loss. Millions of borrowers made this calculation at the same time.

The bundles of mortgages that investors owned suddenly became worthless. A pension fund that thought it owned a safe investment backed by home equity discovered it owned a pile of defaulted loans. The value of these bundles collapsed, and no one knew what price to assign them — maybe they were worth 50 cents on the dollar, maybe 10 cents. No one wanted to buy them at any price.

Banks stopped lending to each other

Banks lend to each other constantly. One bank might have excess cash at the end of the day and lend it overnight to another bank that needs it. This is how the financial system keeps moving. In September 2008, this stopped. Banks did not know which other banks held the bad mortgage bundles, so they did not know which banks were about to fail. Rather than risk lending to a bank that might collapse, they stopped lending altogether.

This created a liquidity crisis — banks had assets but could not convert them to cash. A bank might own a building worth $50 million, but if no one will lend it money and it needs cash to pay depositors, it is in trouble. Several large banks failed. The government intervened with emergency loans and guarantees to prevent a complete collapse of the banking system.

How this affected people with bank accounts

If you had money in a regular savings or checking account at a bank that failed, the Federal Deposit Insurance Corporation (FDIC) protected your money up to $100,000 per account. This protection existed before 2008 and still exists today. During the crisis, the FDIC temporarily raised this limit to $250,000 to reassure depositors.

The real damage to ordinary people came from job losses. When banks failed and the financial system seized up, businesses could not get loans to operate. They laid off workers. Unemployment rose sharply. People lost their homes not just because they could not afford the mortgage, but because they lost their jobs. The crisis spread from the financial system into the real economy.

What regulators and lawmakers changed afterward

Congress passed the Dodd-Frank Act in 2010, which created new rules for banks. Banks now have to keep more capital on hand — money they cannot lend out — so they can absorb losses without failing. They have to stress-test their portfolios, meaning regulators simulate a crisis and make sure the bank could survive it. Banks are no longer allowed to make certain kinds of risky bets with depositors' money.

The Consumer Financial Protection Bureau was created to write rules about mortgages and other consumer loans. Lenders now have to verify that a borrower can actually afford the loan — a rule called the ability-to-repay requirement. A bank cannot write a mortgage to someone without checking their income and debts.

These changes made another 2008-style crisis less likely, though not impossible. The rules are complex and regulators have limited resources. Banks continue to lobby to weaken the rules. But the basic structure — that lenders must verify borrowers can repay, and that banks must hold enough capital to survive losses — remains in place.

Frequently Asked Questions

Did the government bail out the banks?

Yes. The Federal Reserve lent hundreds of billions of dollars to banks at low interest rates. Congress authorized the Troubled Asset Relief Program (TARP), which spent $700 billion buying bad assets from banks and injecting capital directly. Most of this money was repaid, but the government did lose billions on some investments. The bailout was controversial because ordinary people lost their homes and jobs while banks received government support.

Could a crisis like this happen again?

The rules put in place after 2008 make it harder, but financial crises are part of how markets work. Different kinds of crises could still occur — in commercial real estate, in student loans, or in other areas. The key difference is that banks now have to prove they can survive a major loss, and lenders have to verify borrowers can repay.

Why did the government bail out banks but not homeowners?

The government did offer some help to homeowners through loan modification programs and foreclosure prevention efforts, but it was much smaller than the bank bailout. The reasoning was that if banks failed, the entire financial system would collapse and unemployment would be even worse. Many people disagreed with this choice. It remains a point of debate about fairness and how government should respond to crises.

What happened to the people who caused the crisis?

Some executives and traders faced criminal charges, but prosecutions were limited. Most people who made risky decisions or committed fraud were not charged. Some lost their jobs or took pay cuts. This lack of accountability also became controversial and contributed to public anger about the financial system.