Connecticut residents pay roughly 3%–6.99% state income tax on CD interest, depending on bracket. The best CD rates available to CT residents reach that differ by bank and term at FDIC-insured online banks. Connecticut’s income tax environment makes it worth comparing CDs to Treasury bills, which are exempt from CT state income tax.
Bank rates below were read from each bank’s own page, with the date shown under the table. Verify current rates directly with the institution before opening.
Best CD Rates Available to Connecticut Residents (Online Banks, October 2026)
| Institution | Type | 12-Month APY | Min. Deposit |
|---|---|---|---|
| Popular Direct | Online | 4.50% | $10,000 |
| Marcus by Goldman Sachs | Online | 4.40% | $500 |
| EverBank | Online | 3.50% | $1,000 |
Rates read from each bank’s own page: Popular Direct October 5, 2026, Marcus October 15, 2026, EverBank October 9, 2026. These online banks accept customers in any state. We did not check rates at local credit unions and community banks, so they are not listed with rates here; ask them directly.
Connecticut State Income Tax on CD Interest
Connecticut uses a progressive income tax structure ranging from roughly 3% at the lowest bracket to 6.99% at the highest. Confirm the exact current-year bracket thresholds at portal.ct.gov/DRS, since precise dollar thresholds are subject to periodic adjustment.
Illustrative after-tax yield on a hypothetical 4.50% CD for a typical CT resident in the ~5.5% bracket (22% federal + 5.5% CT):
- Total marginal rate: ~27.5%
- After-tax yield: ~3.26%
T-Bills vs. CDs for Connecticut Residents
| 12-Month CD (hypothetical) | 1-Year Treasury | |
|---|---|---|
| Gross yield (hypothetical, same for both) | 4.50% | 4.50% |
| Federal taxable | Yes | Yes |
| CT state taxable (~5.5%, illustrative) | Yes | No |
| After-tax yield (22% federal + 5.5% CT) | ~3.26% | ~3.51% (federal-only) |
The after-tax advantage of Treasuries is meaningful for most CT residents and grows for those in higher brackets.
What $10,000 Earns at Top Available CT Rates
| Term | APY (Popular Direct) | Gross Interest | After-Tax (22% federal + 5.5% CT, illustrative) |
|---|---|---|---|
| 6 months | 4.35% | ~$215 | ~$156 |
| 12 months | 4.50% | ~$450 | ~$326 |
| 2 years | 4.70% | ~$962 | ~$698 |
Figures use Popular Direct’s APYs as of October 5, 2026 (it requires $10,000 to open a CD) and the compounding convention A = P(1+APY)^years.
Notable Connecticut Institutions
- Ion Bank — Naugatuck-based; community bank serving CT residents
- Sikorsky Financial Credit Union — Stratford-based; open to current/former Sikorsky/RTX employees and family members; also open to Fairfield County residents through community membership
- Salisbury Bank — Northwestern CT and Dutchess County, NY; relationship pricing for local customers
- People’s United (now M&T Bank) — Bridgeport-based, now merged into M&T Bank; largest CT-origin bank by assets
Related Articles
The content on Wealthvieu is for informational purposes only and should not be considered financial, tax, or investment advice. Consult a qualified professional before making financial decisions. Full disclaimer · Editorial policy