Bank Gap by State
The Bank Gap in Connecticut
Connecticut's top tax bracket plus a benefit-recapture provision for high earners make the after-tax math on savings interest more involved here than in most states, on top of a cost of living that runs well above the national average.
Last reviewed August 7, 2026 · SwitchWize Research Desk
Before CT tax
$1,005/yr
on a $25,000 balance
After CT 6.99% tax
$935/yr
recoverable by switching
On a $25,000 balance, the gap is about $1,005 a year before tax. After Connecticut's 6.99% top income-tax rate on the additional interest, you keep about $935. Because Treasury interest is exempt from Connecticut income tax, routing that cash through a state-tax-exempt Treasury vehicle can recover most of the difference.
Estimated Bank Gap by balance
| Balance | Current earnings | Better-fit earnings | Estimated Bank Gap | After CT tax |
|---|---|---|---|---|
| $5,000 | $19 | $220 | $201 | $187 |
| $10,000 | $38 | $440 | $402 | $374 |
| $25,000 | $95 | $1,100 | $1,005 | $935 |
| $50,000 | $190 | $2,200 | $2,010 | $1,870 |
| $100,000 | $380 | $4,400 | $4,020 | $3,739 |
Estimates over 12 months at 0.38% current APY and 4.40% better-fit APY. The "After CT tax" column applies CT's 6.99% top income-tax rate to the additional interest; federal tax applies on top and is not shown. Example only — your result depends on your balance, rates, and time horizon.
Why Connecticut changes the math
Connecticut taxes interest income at a top rate of 6.99%, and the state's benefit-recapture rules mean some high earners effectively pay close to the top rate on all their income, including interest. Treasury interest stays exempt from that tax, making T-Bills and government money market funds worth a closer look for higher-income Connecticut savers.
Fairfield County and the broader Connecticut suburbs of New York carry some of the highest living costs in the Northeast, which tends to size emergency funds well above the national norm.
Cost of living in Connecticut is well above the national average, especially in Fairfield County, which shapes how large an emergency fund needs to be and therefore how many dollars the Bank Gap quietly costs on idle cash.
Because Connecticut taxes savings interest but not Treasury interest, the highest after-tax yield is not always the highest headline APY. Run your tax profile through the short-term savings tool to see whether a Treasury bill or government money market fund beats a taxable account for you.
Open the short-term savings toolFrequently asked questions
Does Connecticut tax high-yield savings account interest?
Is a high-yield savings account worth it in Connecticut?
Are T-Bills better than a HYSA for Connecticut savers?
Your personal Bank Gap
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Calculate my Bank GapEducational information, not tax or financial advice. State tax rules are summarized at a high level and depend on your full situation. Rates are illustrative of current market conditions and should be confirmed with the provider. Confirm tax treatment with a qualified professional.