Money Market vs HYSA: The Honest Breakdown

The MMA vs HYSA choice depends on check-writing needs, balance size, and which product your bank prices more competitively.

Money market accounts (MMAs) and high-yield savings accounts (HYSAs) are structurally nearly identical: both are FDIC-insured savings vehicles, both pay variable rates that track the Fed funds rate, both are liquid without a fixed term commitment. The two differences that remain material are check-writing access and rate-tiering.

MMAs typically include check-writing privileges and debit card access. HYSAs at online banks typically do not. If you need to write occasional checks from a savings pool — for a large purchase, a tax payment, or a deposit on a rental — an MMA provides that flexibility. For a pure savings or emergency fund, it is irrelevant.

Rate-tiering is the more consequential difference. Many MMAs apply tiered rates: $0–$9,999 might earn 0.50%, $10,000–$99,999 might earn 4.50%, and $100,000+ might earn 4.75%. If your balance typically sits at $8,000, the MMA's advertised rate does not apply to you. HYSAs at online banks are more often single-rate products (same rate on all balances up to a limit, if any limit exists at all).

The practical guidance: for balances under $25,000 with no check-writing need, a HYSA at an online bank is nearly always the better product. For balances above $50,000, or for balances where check-writing access matters, compare the MMA tier schedule directly against the HYSA rate at the same institution and competitors.

One frequently overlooked option: Fidelity's Cash Management Account (CMA) functions as a checking account but sweeps to either FDIC-insured partner banks or a government money market fund at 4–5% yield. For people comfortable with a brokerage-affiliated product, it competes favorably with both MMAs and HYSAs.