Massachusetts residents pay a flat 5% state income tax on CD interest in 2026 (rising to 9% on income above the $1,107,750 surtax threshold for 2026, per Mass.gov). The best CD rates available to MA residents reach approximately 4.44% APY through FDIC-insured online banks. Massachusetts-based DCU is also a nationally available credit union.

Rates shown are as of September 2026 and change frequently. Verify current rates directly with the institution before opening.

Best CD Rates Available to Massachusetts Residents (September 2026)

Institution Type 12-Month APY Min. Deposit
Online banks (top-rate) Online 4.30–4.44% $0–$10,000
DCU (Digital Federal Credit Union) National CU (MA-based) 3.75–4.25% $500
Metro Credit Union MA credit union 3.50–4.00% $500
Eastern Bank MA regional bank 3.50–4.00% $1,000
Webster Bank Regional bank 3.50–4.00% $1,000
Traditional big banks National bank 0.01–1.00% $1,000+

Massachusetts State Income Tax on CD Interest

Massachusetts has a flat 5% income tax on most income including CD interest. The 4% Surtax on Taxable Income (approved by voters in 2022, often called the “Millionaire’s Tax”) applies to taxable income above an inflation-adjusted threshold — $1,107,750 for tax year 2026, per the Massachusetts Department of Revenue — creating a combined 9% state rate on income above that threshold.

After-tax yield on a 4.35% CD for a typical MA resident (22% federal + 5% MA):

  • Total marginal rate: ~27%
  • After-tax yield: ~3.18%

T-Bills vs. CDs for Massachusetts Residents

Treasury bill interest is exempt from Massachusetts state income tax.

12-Month CD (top rate) 1-Year Treasury
Gross yield ~4.35% ~4.37% (per Fed H.15, Sept 14, 2026)
Federal taxable Yes Yes
MA state taxable (5%) Yes No
After-tax yield (22% federal + 5% MA) ~3.18% ~3.41% (federal-only)

The Treasury’s state tax exemption gives it a modest after-tax edge for most MA residents at these rate levels. For those above the $1,107,750 surtax threshold paying the 9% state rate, Treasuries are more clearly superior.

What $10,000 Earns at Top Available MA Rates

Term APY (top rate) Gross Interest After-Tax (22% federal + 5% MA)
6 months 4.25% ~$210 ~$154
12 months 4.35% ~$435 ~$318
2 years 4.35% ~$889 ~$649

Figures use the APY compounding convention: A = P(1+APY)^years.

DCU — A Massachusetts-Based National Credit Union

DCU (Digital Federal Credit Union) is headquartered in Marlborough, MA and is worth highlighting as a credit union option for CD savers nationwide:

  • Open to all US residents through a small donation to a partner organization — confirm the current process directly with DCU
  • Insurance: NCUA-insured
  • Access: Entirely online; no branch requirement

Other Notable Massachusetts Institutions

  • Metro Credit Union — Chelsea-based; open to residents of greater Boston area
  • Eastern Bank — Boston-based mutual savings bank turned public company; relationship pricing available
  • Rockland Trust — Southeastern MA community bank
  • Needham Bank — Needham-based mutual savings bank; competitive CDs for relationship customers
WealthVieu
Written by WealthVieu

WealthVieu researches and writes data-driven personal finance guides using primary sources including the IRS, Bureau of Labor Statistics, Federal Reserve, and Census Bureau.

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