With interest rates at historic lows, many financial experts argue that having some debt today isn’t necessarily a bad thing. For instance, if your debt carries an interest rate of around 3%, it may not make sense to pull money from investments earning 6% or more just to pay it off. You’d essentially lose the higher return in favor of paying down a relatively low-cost loan.
This concept relates to something banks use every day: arbitrage. Arbitrage is the practice of taking advantage of price or interest rate differences between two or more markets.
Let’s break it down with a simple example. Suppose you deposit $100,000 into a bank account, and the bank offers you 0.5% interest. The bank then takes your money and lends it out to other customers at a higher rate—say, 4%. While you earn 0.5%, the bank earns the 3.5% difference. That’s arbitrage in action.