Walk into any bank branch and you will encounter one of capitalism's quieter absurdities: the institution will offer you a savings account paying a fraction of a percent while simultaneously advertising personal loans at double-digit rates. The spread between these two numbers is not a bug in the system but its defining feature, and understanding why it persists explains much about how ordinary people subsidize the financial architecture around them.
The technical term is the net interest margin, and it represents the difference between what a bank earns on loans and investments versus what it pays depositors. For most of modern banking history, this margin has been remarkably stable and remarkably generous to the banks. Even when central banks raise rates aggressively, retail savings accounts tend to lag far behind, sometimes for years.
The stickiness problem
Economists call this phenomenon deposit beta, a measure of how much of a central bank rate increase gets passed through to savers. The number is almost never one hundred percent, and for basic savings accounts at large retail banks, it often hovers around thirty to forty percent. A two-percentage-point rate hike might translate into less than one point for the average saver.
The reasons are structural rather than conspiratorial. Retail depositors display remarkable inertia. Moving a savings account requires effort, and the absolute dollar amounts involved rarely justify the hassle for most households. A family with ten thousand in savings might gain an extra hundred annually by switching to a higher-yield account, but the cognitive cost of researching alternatives, opening new accounts, and managing the transition exceeds the benefit for many people. Banks know this intimately.
The competition that isn't
Traditional banks also benefit from bundling. Your savings account exists alongside your checking account, your mortgage, your credit card. The relationship creates switching costs that extend far beyond any single product. Online-only banks and money market funds occasionally disrupt this equilibrium by offering genuinely competitive rates, but they struggle to achieve the kind of market penetration that would force legacy institutions to respond meaningfully.
The result is a two-tier system. Financially sophisticated households park their excess cash in treasury bills, money market funds, or high-yield online accounts. Everyone else accepts whatever their primary bank offers, which is typically far less. This gap represents a quiet wealth transfer from the financially passive to the financially active, compounding over decades.
Our take
The persistence of near-zero savings rates during periods of elevated interest rates is not market failure in the classical sense. It is the market working exactly as designed, rewarding attention and punishing inertia. The uncomfortable truth is that your bank's low savings rate is not an oversight; it is a business model predicated on the reasonable assumption that you will not bother to leave. For most people, that assumption proves correct, and the banks collect the difference.
