🏦 Where should I park my cash?
🏁 Overview
Parking $20,000 in a checking account earns nothing, but moving it to a safe, yield-bearing asset generates hundreds of dollars a year. This calculator compares one year of after-tax interest across three popular cash options to find your absolute highest return without market risk.
🏛️ Taxes & Timing
TreasuryDirect sells T-bills in terms ranging from 4 to 52 weeks at a discount to face value, with a minimum purchase of $100. Federal tax applies to the interest, but Treasuries are completely exempt from state and local income taxes.
This tax shield makes T-bills highly competitive for savers in high-tax states. Bank products lack this exemption, meaning their earnings face both federal and state taxes.
📈 Rates & Options
Keep cash in an HYSA for total flexibility, lock in a CD for a fixed term, or buy T-bills when state income taxes drag down bank returns. All three are extremely safe, backed by FDIC insurance or the U.S. government.
To keep things simple, this model looks at a single year at today's rates. It ignores rate changes at CD maturity or T-bill rollover risk, and excludes CDs entirely if you need access to the money.
HYSA Math
CD Math
T-Bill Math
Winner Math
🔗 See Also
For further related reading, check out:
📊 Results
HYSA After-Tax
CD After-Tax
T-Bill After-Tax
Best Option
T-bills
Last updated by heyfinfam (v26.7.0) · View history
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Disclaimer: This content and any calculations provided are for informational purposes only. The views, calculations, and methodologies expressed are those of the author and do not necessarily reflect those of this platform. Not financial advice. Users are solely responsible for any decisions made based on this information.
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