What Idle Cash Costs: The Opportunity Cost of Holding Money

Introduction

When Berkshire Hathaway’s new CEO Greg Abel moved a record chunk of the company’s cash pile in Q2 2026 — investing $10 billion in Google’s parent company and buying back about $4.5 billion of shares — the financial press described it as the end of an era. For years, the conglomerate had sat on a mountain of cash that peaked near $400 billion. Why would anyone hold that much money doing nothing? And why did it start moving when it did?

The answer is a concept that quietly drives most financial decisions: opportunity cost. Holding cash is never free. Every dollar sitting idle forgoes the interest it could earn in a deposit, a government bond, or a productive investment. The price of that forgone return — measured most directly by the deposit interest rate — is what this explainer unpacks. For the full data picture across 113 economies, see our report on the price of idle cash.

What a deposit rate measures

The deposit interest rate is what banks pay on savings deposits — the price a bank offers for the right to hold your money. The World Bank tracks it as indicator FR.INR.DPST across 113 economies, and the global range is enormous:

• In Turkiye, a deposit paid 71.0% in 2024.
• In Brazil, it paid 7.7%.
• In Switzerland, 0.9%.
• In Singapore, 0.1%.
• In Micronesia, 0.0%.

That 700-to-1 range between the top and bottom is not mostly about generosity — it is mostly about inflation, currency risk, and central bank policy. Where prices are rising fast, nominal rates must be high just to keep deposits attractive; where inflation is low and stable, near-zero rates are enough. The number that actually matters to a saver is the real rate — the nominal rate minus inflation. A 71% nominal rate in Turkiye with inflation running above 60% can leave savers losing purchasing power; a 0.9% rate in Switzerland with near-zero inflation preserves it. We explore this gap in detail in why high deposit rates don’t mean savers win.

Why cash hoards form

A deposit rate is also the price of not deciding. When that price is high, holding cash is attractive and hoards grow. That is exactly what happened globally after 2022: central banks raised rates aggressively to fight inflation, and the yield on idle cash jumped. For a company like Berkshire, sitting on cash was suddenly a strategy — the hoard earned meaningful interest while waiting for opportunities, and it cushioned against market shocks. The same logic applied to households and banks, which is why bank deposits ballooned relative to GDP in many economies.

But hoards also form for reasons that have nothing to do with yield. Banks in crisis economies hold enormous cash buffers because they cannot find creditworthy borrowers — see our analysis of how liquid the world’s banks are. Households in countries with thin safety nets save defensively, not opportunistically. And companies accumulate cash when they distrust the investment environment, when they anticipate acquisitions, or simply when they have no better use for it. The deposit rate tells you what hoarding pays; it doesn’t tell you why the hoard formed.

Why hoards move

The flip side is what happened in 2024–2026: rates began falling, and the calculus flipped. Our trend data shows deposit rates rolling over across much of Latin America and Central Europe — Brazil fell from 12.1% to 7.7%, Chile from 10.4% to 6.1%, Hungary from 13.1% to 6.2%, Colombia from 13.2% to 10.2% between 2023 and 2024.

When the yield on cash falls, three things happen:

1. The opportunity cost of holding rises. If a deposit pays less, every month of waiting forgives more potential return elsewhere — so the pressure to deploy grows.
2. Asset prices respond. Lower rates make future earnings worth more today, which is one reason stock markets tend to strengthen when rate expectations fall. For how that plays out at the country level, see our explainer on how central bank rates shape borrowing.
3. Banks reprice credit. Falling deposit rates usually pull lending rates down with them, making borrowing cheaper — the mechanism behind the deposit-credit wedge narrowing. Cheaper credit, in turn, is what lets households and firms finance formal savings and investment rather than just accumulating cash.

Berkshire’s Q2 2026 deployment — the biggest quarterly reduction in its cash pile in years — is the corporate-scale version of this logic. When the price of idle cash falls far enough, even the world’s most patient investor starts putting money to work.

What the data can and cannot tell you

Deposit rate data has real limits worth keeping in mind:

• Coverage gaps. Many advanced economies — the United States, the United Kingdom, Germany, France, Japan, India — do not report this indicator to the World Bank, so their absence from the ranking says nothing about their actual rates. For U.S. and European rate context, see our global interest rate map.
• Nominal vs. real. The headline number is nominal. Comparing deposit rates across economies without adjusting for inflation can be deeply misleading — Zimbabwe’s 17.9% and Kenya’s 12.0% are not “better deals” than South Korea’s 3.5% in real terms.
• Averages, not products. The rate is typically a weighted average across banks and maturities. Actual offers vary.
• The spread matters too. What a bank pays depositors is only half the story; what it charges borrowers is the other. The gap — the bank interest rate spread — is where the cost of intermediation shows up.

Sources & method

This explainer draws on the World Bank’s World Development Indicators: the deposit interest rate (indicator FR.INR.DPST, 113 economies) and the lending interest rate (FR.INR.LEND), with trend values from the time series in our derived datasets. Berkshire Hathaway’s cash and deployment figures are from the company’s Q2 2026 earnings report as covered by the Associated Press. See our methodology page for how we source, validate, and present World Bank data, and our companion report on the price of idle cash for the full ranking and trend tables.