Money Market Funds vs. Business Savings Accounts

What each is

A business savings account is a deposit account at an FDIC-insured bank, paying interest at a rate the bank sets. Principal is FDIC-insured up to \$250,000 per depositor per insured bank. Withdrawals are typically unlimited.

A money-market mutual fund is an investment in short-term debt securities (Treasury bills, commercial paper). It's not FDIC-insured, but the largest funds (Vanguard Federal Money Market, Fidelity Government Money Market) hold mostly US Treasury debt, which is functionally as safe as bank deposits in most scenarios.

Yield and access

In a 5% Fed Funds rate environment, money-market funds typically yield 4.7-5.0%; high-yield business savings accounts yield 3.5-4.5%; and standard checking accounts yield close to 0%. The yield gap is large enough that any cash held more than 30 days should be in one of the two higher-yielding options.

Access timing differs: money-market funds at brokerages settle T+1 (next business day) for transfers to a checking account; bank savings transfers settle same-day or next-day. For genuine emergency reserves, prefer the same-bank savings option for instant access; for deeper reserves, the brokerage money-market is fine and yields more.

Deciding where to park cash

For business reserves, the choice is usually between a high-yield business savings account, a money market deposit account (MMDA), and a money market mutual fund (MMMF). Savings accounts and MMDAs are FDIC-insured up to $250k per depositor per bank; mutual funds are not insured but invest in very short-duration government or commercial paper and have a long history of holding their $1 NAV.

For balances above $250k, the practical solutions are either a sweep program that distributes deposits across multiple banks (IntraFi/CDARS or similar) or a treasury money-market mutual fund holding only US Treasury securities, which carries effectively no credit risk. Both options preserve full liquidity while removing single-bank concentration risk — which became a top-of-mind issue after the 2023 regional banking turmoil.

Compare yields net of fees and net of access friction. A 5.0% MMMF that requires 2 days to get cash to your operating account is functionally equivalent to a 4.7% savings account that's instant — once you account for the inability to use the higher-yielding account in an emergency.

For very large balances (>$5M), engage a treasury management specialist. Bond ladders, short-duration municipal portfolios, and direct treasury holdings all become viable at scale and can add another 50-150 basis points over money-market funds with carefully managed risk. Below that threshold, the operational complexity rarely justifies the marginal yield, and a high-yield savings or sweep money-market is usually optimal.