The Federal Reserve’s 0.25 percentage-point rate increase is raising borrowing costs first for households with variable-rate debt, particularly credit cards and home equity lines of credit (HELOCs). A cardholder with the average $6,600 balance would pay about $1.38 more in monthly interest, while the $459.3 billion in outstanding HELOC balances could generate as much as $1.15 billion in additional annual repayment costs if the prime rate rises by the same amount. Mark Fleming, chief economist at First American, said greater reliance on home equity to repay other debt could amplify pressure from higher credit-card rates and contribute to mortgage delinquencies. Mortgage and auto-loan costs are less directly tied to the Fed’s short-term policy rate, with Cox Automotive estimating monthly payment increases of about $6 for new vehicles and $4 for used ones if the full increase is passed through. Homebuilders face different exposures depending on their financing, while higher mortgage rates could make subsidized financing more expensive. Investment-grade corporate bond yields have already risen to 5.8% from about 5.4% a month earlier, meaning borrowing costs may not rise much further if expectations for additional Fed hikes remain unchanged. The wider financial-market effect will depend on future Fed decisions and long-term Treasury yields, while depositors could benefit if banks pass higher policy rates through to deposit accounts.