Connecticut Income Tax Rate 2017 - 2018

Connecticut state income tax rate table for the 2017 - 2018 filing season has seven income tax brackets with CT tax rates of 3%, 5%, 5.5%, 6%, 6.5%, 6.9% and 6.99% for Single, Married Filing Jointly, Married Filing Separately, and Head of Household statuses. The Connecticut tax rate and tax brackets are unchanged from last year.

Connecticut income tax rate and tax brackets shown in the table below are based on income earned between January 1, 2017 through December 31, 2017. Outlook for the 2018 Connecticut income tax rate is to remain unchanged.

Single Tax BracketsTax Rate 2017
Source: 2017 Connecticut Tax Calculation Table, published by the State of Connecticut Department of Revenue Services.
$0to$10,0003%
$10,001to$50,0005%
$50,001to$100,0005.5%
$100,001to$200,0006%
$200,001to$250,0006.5%
$250,001to$500,0006.9%
$500,001to6.99%
Married Filing Jointly BracketsTax Rate 2017
Source: 2017 Connecticut Tax Calculation Table, published by the State of Connecticut Department of Revenue Services.
$0to$20,0003%
$20,001to$100,0005%
$100,001to$200,0005.5%
$200,001to$400,0006%
$400,001to$500,0006.5%
$500,001to$1,000,0006.9%
$1,000,001to6.99%
Married Filing Separately BracketsTax Rate 2017
Source: 2017 Connecticut Tax Calculation Table, published by the State of Connecticut Department of Revenue Services.
$0to$10,0003%
$10,001to$50,0005%
$50,001to$100,0005.5%
$100,001to$200,0006%
$200,001to$250,0006.5%
$250,001to$500,0006.9%
$500,001to6.99%
Head of Household BracketsTax Rate 2017
Source: 2017 Connecticut Tax Calculation Table, published by the State of Connecticut Department of Revenue Services.
$0to$16,0003%
$16,001to$80,0005%
$80,001to$160,0005.5%
$160,001to$320,0006%
$320,001to$400,0006.5%
$400,001to$800,0006.9%
$800,001to6.99%

Please reference the Connecticut tax forms and instructions booklet published by the State of Connecticut Department of Revenue Services to determine if you owe state income tax or are due a state income tax refund. Connecticut income tax forms are generally published at the end of each calendar year, which will include any last minute 2017 - 2018 legislative changes to the CT tax rate or tax brackets. The Connecticut income tax rate tables and tax brackets shown on this web page are for illustration purposes only.

Connecticut Tax Brackets 2017 - 2018

Looking at the tax rate and tax brackets shown in the tables above for Connecticut, we can see that Connecticut collects individual income taxes differently for Single versus Married filing statuses, for example. We can also see the progressive nature of Connecticut state income tax rates from the lowest CT tax rate bracket of 3% to the highest CT tax rate bracket of 6.99%.

For single taxpayers living and working in the state of Connecticut:

  • Tax rate of 3% on the first $10,000 of taxable income.
  • Tax rate of 5% on taxable income between $10,001 and $50,000.
  • Tax rate of 5.5% on taxable income between $50,001 and $100,000.
  • Tax rate of 6% on taxable income between $100,001 and $200,000.
  • Tax rate of 6.5% on taxable income between $200,001 and $250,000.
  • Tax rate of 6.9% on taxable income between $250,001 and $500,000.
  • Tax rate of 6.99% on taxable income over $500,000.

For married taxpayers living and working in the state of Connecticut:

  • Tax rate of 3% on the first $20,000 of taxable income.
  • Tax rate of 5% on taxable income between $20,001 and $100,000.
  • Tax rate of 5.5% on taxable income between $100,001 and $200,000.
  • Tax rate of 6% on taxable income between $200,001 and $400,000.
  • Tax rate of 6.5% on taxable income between $400,001 and $500,000.
  • Tax rate of 6.9% on taxable income between $500,001 and $1,000,000.
  • Tax rate of 6.99% on taxable income over $1,000,000.

For the Single, Married Filing Jointly, Married Filing Separately, and Head of Household filing statuses, the CT tax rates and the number of tax brackets remain the same. Notice, however, the Connecticut income tax brackets for Married Filing Jointly double from $10,000 to $20,000 at 5%, and double from $500,000 to $1,000,000 at 6.99% the highest tax bracket. Married Filing Separately income tax brackets are one half that of the Married Filing Jointly income tax brackets in the state of Connecticut.

Last updated: October 15, 2017