Work in Connecticut, Live in Massachusetts: Taxes, Credits and Remote Days

Reciprocity

Do Connecticut and Massachusetts have a tax reciprocity agreement?

No. Connecticut's Department of Revenue Services (DRS) uses this exact commute as its example: a resident of Massachusetts works in Connecticut for an employer doing business in both states, and DRS says the employer is required to withhold Connecticut income tax because the services are performed in Connecticut.

Massachusetts accepts that result and prevents double tax from its own side. The Department of Revenue says Massachusetts residents who work and pay income taxes in other states are generally entitled to a credit against their Massachusetts income taxes. Its withholding directive for residents with out-of-state jobs even uses a Massachusetts resident working in Connecticut as the example. Two states tax the same pay, and the Massachusetts credit takes out the overlap.

Our state reciprocity agreements list shows which states do trade withholding with their neighbors.

Returns

Which returns does a Massachusetts resident with a Connecticut job file?

Two. Connecticut's return is Form CT-1040NR/PY. For the 2025 taxable year you must file it if Connecticut tax was withheld from your pay, or if you had Connecticut-sourced income and meet the gross income test. Gross income counts income from inside and outside Connecticut, so your Massachusetts income helps you cross the line. The 2025 thresholds were:

The 2025 return was due on or before April 15, 2026; check DRS for 2026 figures. In Massachusetts, the nonresident regulation assigns Form 1 to residents and Form 1-NR/PY to nonresidents and part-year residents. You are a resident if you are domiciled in Massachusetts, or if you keep a permanent place of abode there and spend more than 183 days of the tax year in the state. Do the Connecticut return first, because the Massachusetts credit needs the Connecticut tax figure.

CT tax

How does Connecticut calculate tax on a nonresident's wages?

Connecticut does not have a separate nonresident rate table. The CT-1040NR/PY instructions say nonresidents calculate the tax in the same manner as resident individuals, then prorate it based on the percentage of their Connecticut adjusted gross income derived from Connecticut sources. On the form, Line 9 holds that ratio and Line 10 multiplies the Line 8 tax by it.

For the 2025 taxable year, the schedule for single filers starts at 2.00% on the first $10,000, charges 4.5% on the excess over $10,000 in the next band, and reaches 6.99% on the excess over $500,000. Because the tax is first figured on all your income, Massachusetts wages or investment income can push the Connecticut rate up even though Connecticut keeps only its prorated share.

Wages are sourced by working days. Days you were not required to work, such as holidays, sick days, vacations and paid or unpaid leave, are left out of the count. On the return, a day spent partly inside and partly outside Connecticut counts as one half inside. Short trips have their own rule: pay for 15 days or less of work in Connecticut in a year is not Connecticut-sourced income. If you were expected to stay under that limit but go over it, the employer must withhold on all the Connecticut pay, including the first 15 days.

The credit

How does Massachusetts credit the Connecticut tax?

You claim it on Form 1, your annual Massachusetts resident return. It rests on G.L. c. 62, section 6(a), which the Department of Revenue describes as a credit allowed to a resident for taxes due any other state on account of any item of Massachusetts gross income. Your Connecticut wages are part of that income. Nonresidents cannot claim it, because Massachusetts taxes them only on Massachusetts source income.

The credit is capped. In a 2012 directive on Rhode Island taxes, the Department described the computation as a comparison between the Massachusetts income tax on the income reported to the other state and the tax actually paid there, with the credit limited to the smaller of these two amounts. If Connecticut's prorated tax is lower than the Massachusetts tax on the same wages, you owe Massachusetts the gap. If it is higher, the credit stops at the Massachusetts figure.

Connecticut offers nothing in return. Its instructions say nonresidents may not claim a credit for income taxes paid to other jurisdictions, so the Massachusetts credit is the only relief. Very high earners should also factor in the Massachusetts 4% surtax on the portion of taxable income that exceeds $1,000,000, adjusted annually for inflation.

On the 2025 Massachusetts Form 1 the credit goes on line 30 with Schedule OJC, Income Tax Due to Other Jurisdictions, and it does not apply to city or local taxes. If Massachusetts tax is not withheld, estimated payments are due from anyone who expects to pay more than $400 of Massachusetts income tax not covered by withholding.

Withholding

How should payroll handle CT-W4, CT-W4NA and Massachusetts withholding?

Connecticut payroll starts with Form CT-W4, which employers must collect from each new employee when hired. If you split your week between a Connecticut office and your Massachusetts home, the second form matters more: Form CT-W4NA, the nonresident apportionment certificate. Circular CT tells employers they must withhold Connecticut income tax on all wages paid to the employee unless they can properly allocate the Connecticut share, either through a CT-W4NA or adequate current records. No certificate and no day records means Connecticut withholding on all of your pay.

Give payroll a new CT-W4NA whenever your Connecticut percentage changes from the one on file. One quirk: on the CT-W4NA worksheet a day spent partly inside Connecticut counts as entirely inside, while the return counts it as one half. The certificate only sets withholding. Circular CT says the percentage does not determine the tax due on the CT-1040NR/PY, which uses the actual days you worked in Connecticut.

On the Massachusetts side, 830 CMR 62B.2.1 tells an employer to withhold the Massachusetts amount less the Connecticut amount required on the same wages. If Connecticut's amount equals or exceeds the regular Massachusetts amount, no Massachusetts tax should be withheld. For 2026, DRS says its withholding calculation rules and tables are unchanged from 2025.

If you work for a covered Connecticut employer, you also contribute to CT Paid Leave: 0.5% of your income up to the Social Security contribution limit, a rate the program's board kept at 0.5% for 2026.

Worked example: sourcing a hybrid salary to Connecticut

Hypothetical salary and day counts, using the working day method and Line 9 ratio from the 2025 CT-1040NR/PY instructions. Assumes the salary is your only income. Illustrative only.

Remote work

What if you work from home in Massachusetts for a Connecticut employer?

Home days start outside Connecticut's reach. DRS says wages of a nonresident are not subject to Connecticut withholding if paid for services performed entirely outside Connecticut. In its example, an employer whose payroll department is in Connecticut is not required to withhold Connecticut tax for a nonresident who works entirely out of state, even though payment is made from a point in Connecticut. A fully remote Massachusetts employee of a Connecticut company should not see Connecticut withholding.

Hybrid schedules raise the question of Connecticut's convenience rule. For taxable years beginning on or after January 1, 2019, residents of states with a convenience of the employer test are subject to similar rules for work performed for a Connecticut employer. Under that kind of test, a nonresident's wages are allocated to the employer's location unless the out-of-state work is due to the employer's necessity rather than the employee's convenience.

Whether that reaches you depends on Massachusetts law. The Massachusetts pandemic telecommuting rule, 830 CMR 62.5A.3, was tied to the emergency: it covered services from March 10, 2020 through 90 days after the Massachusetts COVID-19 state of emergency ended. If payroll sources your home days to Connecticut, ask DRS how it currently treats Massachusetts residents and keep a day-by-day work log.

Connecticut applies that rule to residents of states that use a similar test, and its own example of such a state is New York. Massachusetts' current rule counts only the days a nonresident physically works in Massachusetts, so Connecticut's rule most likely does not reach Massachusetts residents. No Connecticut source names Massachusetts either way, and the CT-W4NA worksheet asks for remote days without that qualification, so keep a clear record of where you worked each day. Days spent on ancillary activities are not counted as Connecticut working days.

Moving

What changes if you move between Massachusetts and Connecticut mid-year?

The move date divides the year between the two states. Connecticut part-year residents file Form CT-1040NR/PY with Schedule CT-1040AW, the Part-Year Resident Income Allocation. Part-year residents may not apportion income earned while they were residents of Connecticut, so all pay from the Connecticut resident period is taxed there, wherever you worked. If some of that income was also taxed by another state during your Connecticut residency, Connecticut may give a credit for the residency portion. Massachusetts assigns Form 1-NR/PY to part-year residents.

Payroll forms change too. Circular CT says you must complete a CT-W4NA when your residency status changes from resident to nonresident, so file one on the day your Massachusetts move is complete if you keep working partly in Connecticut.

Payroll errors

What if the wrong amount or the wrong state's tax was withheld?

• Connecticut tax on all of your pay: This usually means no CT-W4NA was on file. File one now, and on the CT-1040NR/PY report Connecticut-sourced wages based on the actual days worked in Connecticut; the excess withholding is settled on that return.
• No Connecticut tax on Connecticut days: Tax is still owed for those days. Ask payroll to start withholding, and expect the employer to cover the first 15 days too if you passed the short-trip limit.
• Full Massachusetts withholding on top of Connecticut withholding: Ask for the 830 CMR 62B.2.1 reduction. Any over-withholding comes back when you file Form 1.
• One W-2 with two state lines: The Massachusetts tax withheld during the year should appear on your annual Form W-2 alongside the Connecticut figures. That is one set of wages; enter the job once so Form 1 does not count the pay twice.

This is general information, not tax advice.