RSU tax rate in Connecticut: state, federal, and FICA on vest income

Searches for an RSU tax rate in Connecticut usually mean you want one percentage to plan cash for a vest — but Connecticut does not publish a separate equity rate. RSU vest FMV is taxed as ordinary wages under progressive Connecticut DRS brackets, and your effective rate depends on total taxable income for the year, not the vest alone.

Federal progressive income tax and FICA apply on top of Connecticut state tax. FICA runs nationwide on vest wages with Social Security stopping at the annual wage base and Medicare applying to the full amount. Employer supplemental withholding on equity often uses flat methods that can under-withhold compared with your true stacked marginal rate on salary plus vest.

Stamford finance, Hartford insurance, and Fairfield County commuters generate most Connecticut RSU planning questions. Connecticut applies a high-earner tax surcharge on income above thresholds in current law — large RSU vest stacks on high salary may trigger surcharge exposure beyond base bracket rates. Vest planning should use official Connecticut DRS publications for your filing year rather than a single percentage from an old blog post.

Moving from Connecticut to Florida mid-year removes Connecticut state tax on post-move vests for typical Florida residents, but vests while you were a Connecticut resident generally stay Connecticut-connected. Moving from New York to Connecticut changes the state layer on post-move vests. Tri-state commuters comparing NY, NJ, and CT should model credit and sourcing rules on the full return, not just withholding on the vest pay stub.

The practical planning number is a combined estimate: Connecticut marginal state rate plus any high-earner surcharge exposure per current DRS guidance, plus federal marginal rate plus remaining FICA on the vest FMV. Use the Connecticut RSU tax guide for mechanism detail and the RSU tax calculator with Connecticut selected for a stacked-income estimate.

• ✓CT state withholding on vest pay stub.
• ✓W-2 CT wage and tax boxes.
• ✓Federal Box 1 and withholding.
• ✓CT marginal rate with total income for filing year.
• ✓Federal withholding gap vs marginal rate.
• ✓Move date if part-year CT.
• ✓Calculator output vs pay stub.

• ✓CT vest pay stub.
• ✓W-2 CT boxes.
• ✓Vest confirmation.
• ✓CT estimated tax if made.
• ✓Move docs if part-year.

• ✓Part-year CT resident with large equity income.
• ✓CT-NY cross-border vest with conflicting W-2 state boxes.
• ✓Employer withheld wrong state on CT resident vest.
• ✓Multi-state remote work allocation.