Mercury – Mercury Treasury

4.05% headline (up to)

ProductMercury Treasury
TypeGov't money market fund (MRGXX) and ultra-short bond fund (MCRYX)
Yield detail$250K–2M: 3.28% MMF / 3.60% ultra-short · $20–50M: 3.73% / 4.05% (net of fees)
Yield as of2026-10-09 (re-checked 2026-10-17, unchanged)
Minimum$250,000 across Mercury accounts
Fees0.15%–0.60%/yr of Treasury positions (yields shown net)
LiquidityMMF same day if by 3pm ET; ultra-short 1–2 business days (up to 4)
Insurance / protectionSIPC up to $500K (incl. $250K cash) via Apex Clearing; not FDIC. Checking/savings: up to $5M FDIC via sweep

Source: https://mercury.com/treasury (checked 2026-10-16).

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Not financial advice. IdleCash is an independent, informational comparison. We are not a bank, broker or adviser. The comparison table is always sorted purely by the data; sponsorship never changes rank. Yields are variable, quoted as each provider advertises them, and may have changed. Securities products are not FDIC-insured and can lose value. Verify on the provider's site before acting.