--- title: "Money Market Funds, Explained, and How They Differ From Your Savings Account" description: "Cash has poured into money market funds as investors turn cautious. Here's what they actually are, the yields they offer — and the critical difference between a money market fund and an FDIC-insured bank account." category: "Personal Finance" category_url: https://boursel.com/category/personal-finance author: "Daniel Okonkwo" published: 2026-06-26T16:48:00.000Z updated: 2026-06-26T16:48:00.000Z canonical: https://boursel.com/article/money-market-funds-explained-and-how-they-differ-from-your-savings-account tags: ["money-market-funds", "savings", "cash", "fdic", "personal-finance"] --- # Money Market Funds, Explained, and How They Differ From Your Savings Account Cash has poured into money market funds as investors turn cautious. Here's what they actually are, the yields they offer — and the critical difference between a money market fund and an FDIC-insured bank account. *This is general information, not investment advice.* When markets wobble, money pours into "money market funds." It's worth knowing exactly what they are — and what protects them. ## What it is A **money market fund** is a type of mutual fund that holds very short-term, high-quality debt — Treasury bills, government securities, commercial paper, repurchase agreements, short-term CDs — aiming to preserve principal, stay liquid, and pay a yield close to short-term interest rates. Funds are built to hold a stable **net asset value (NAV) of $1.00 per share**, so each dollar in is meant to come back as a dollar plus interest. The **SEC** regulates them under Rule 2a-7, which limits the credit quality, maturity and liquidity of what they can hold. ## Why people use them They're a place to park cash that earns a real yield while staying accessible. When short-term rates are high — as after the Fed's 2022–24 hiking cycle — money fund yields often beat bank savings accounts. And in **risk-off** stretches, investors move cash out of stocks into money funds, exactly the pattern behind this week's big money-fund inflows and equity outflows. Total US money fund assets have reached record levels, crossing roughly **$7 trillion** in recent years, per Investment Company Institute data (figures move weekly). ## The distinction that trips people up This is the most important point. A **money market FUND** is an investment product from an asset manager (Fidelity, Vanguard, Schwab). It is **not a bank deposit and not FDIC-insured** — if it lost value, no government guarantee makes you whole. A **money market DEPOSIT ACCOUNT (MMDA)** at a bank looks similar but **is** FDIC-insured up to $250,000 per depositor, per institution. The [SEC's Investor.gov](https://www.sec.gov/investor/alerts/mmf-investorbulletin.pdf) is explicit that money market funds "are not guaranteed or insured by the FDIC." Same-ish name, fundamentally different products. ## Types - **Government/Treasury funds:** only US government securities and repos — lowest credit risk, common in brokerage cash sweeps. - **Prime funds:** also hold short-term corporate/bank debt — slightly higher yield, marginally more risk. - **Tax-exempt/municipal funds:** short-term muni debt; income often federally tax-exempt. ## The one risk: "breaking the buck" Money funds are very low risk, not zero. The danger is **breaking the buck** — the NAV falling below $1.00. It's rare but real: in **September 2008**, the **Reserve Primary Fund** held Lehman Brothers commercial paper; when Lehman failed, its NAV fell to **$0.97**, triggering a run on money funds and emergency government backstops. The episode led to SEC reforms — tighter maturity and liquidity rules, and a **floating NAV** for institutional prime and tax-exempt funds. ## How yields move Money fund yields track short-term rates closely: they rise when the Fed hikes and **fall when the Fed cuts**. Investors who chased 4–5% yields in 2023–24 should expect that to compress as the rate cycle turns — not a flaw, just the short-duration design working as intended. ## How it compares - **Money market fund:** market-rate yield, **not** FDIC-insured, next-day liquidity. - **High-yield savings / MMDA (bank):** FDIC-insured to $250k, easy access. - **CD:** fixed rate locked in, FDIC-insured, penalty for early withdrawal. - **Treasury bills:** backed by the US government, sold at auction, tradable. ## What it means for savers Money market funds are legitimate, well-regulated, useful cash tools, and the practical risk of losing principal in a government fund is very low. But "very low" isn't "zero," and the absence of FDIC insurance is a genuine structural difference worth understanding before you choose between a fund and an insured bank account. Know what you own, know what protects it — and remember the yield advantage narrows when the Fed cuts. ## Sources - [Money Market Funds — Investor Bulletin](https://www.sec.gov/investor/alerts/mmf-investorbulletin.pdf) - [What is a money market fund?](https://www.fidelity.com/learning-center/investment-products/mutual-funds/what-is-money-market-fund)